Coverage for python/astro_metadata_translator/observationInfo.py: 15%

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1# This file is part of astro_metadata_translator. 

2# 

3# Developed for the LSST Data Management System. 

4# This product includes software developed by the LSST Project 

5# (http://www.lsst.org). 

6# See the LICENSE file at the top-level directory of this distribution 

7# for details of code ownership. 

8# 

9# Use of this source code is governed by a 3-clause BSD-style 

10# license that can be found in the LICENSE file. 

11 

12"""Represent standard metadata from instrument headers""" 

13 

14from __future__ import annotations 

15 

16__all__ = ("ObservationInfo", "makeObservationInfo") 

17 

18import copy 

19import itertools 

20import json 

21import logging 

22import math 

23from typing import ( 

24 TYPE_CHECKING, 

25 Any, 

26 Callable, 

27 Dict, 

28 FrozenSet, 

29 MutableMapping, 

30 Optional, 

31 Sequence, 

32 Set, 

33 Tuple, 

34 Type, 

35) 

36 

37import astropy.time 

38from astropy.coordinates import AltAz, SkyCoord 

39 

40from .headers import fix_header 

41from .properties import PROPERTIES, PropertyDefinition 

42from .translator import MetadataTranslator 

43 

44if TYPE_CHECKING: 44 ↛ 45line 44 didn't jump to line 45, because the condition on line 44 was never true

45 import astropy.coordinates 

46 import astropy.units 

47 

48log = logging.getLogger(__name__) 

49 

50 

51class ObservationInfo: 

52 """Standardized representation of an instrument header for a single 

53 exposure observation. 

54 

55 There is a core set of instrumental properties that are pre-defined. 

56 Additional properties may be defined, either through the 

57 ``makeObservationInfo`` factory function by providing the ``extensions`` 

58 definitions, or through the regular ``ObservationInfo`` constructor when 

59 the extensions have been defined in the ``MetadataTranslator`` for the 

60 instrument of interest (or in the provided ``translator_class``). 

61 

62 Parameters 

63 ---------- 

64 header : `dict`-like 

65 Representation of an instrument header accessible as a `dict`. 

66 May be updated with header corrections if corrections are found. 

67 filename : `str`, optional 

68 Name of the file whose header is being translated. For some 

69 datasets with missing header information this can sometimes 

70 allow for some fixups in translations. 

71 translator_class : `MetadataTranslator`-class, optional 

72 If not `None`, the class to use to translate the supplied headers 

73 into standard form. Otherwise each registered translator class will 

74 be asked in turn if it knows how to translate the supplied header. 

75 pedantic : `bool`, optional 

76 If True the translation must succeed for all properties. If False 

77 individual property translations must all be implemented but can fail 

78 and a warning will be issued. 

79 search_path : iterable, optional 

80 Override search paths to use during header fix up. 

81 required : `set`, optional 

82 This parameter can be used to confirm that all properties contained 

83 in the set must translate correctly and also be non-None. For the case 

84 where ``pedantic`` is `True` this will still check that the resulting 

85 value is not `None`. 

86 subset : `set`, optional 

87 If not `None`, controls the translations that will be performed 

88 during construction. This can be useful if the caller is only 

89 interested in a subset of the properties and knows that some of 

90 the others might be slow to compute (for example the airmass if it 

91 has to be derived). 

92 

93 Raises 

94 ------ 

95 ValueError 

96 Raised if the supplied header was not recognized by any of the 

97 registered translators. Also raised if the request property subset 

98 is not a subset of the known properties. 

99 TypeError 

100 Raised if the supplied translator class was not a MetadataTranslator. 

101 KeyError 

102 Raised if a required property cannot be calculated, or if pedantic 

103 mode is enabled and any translations fails. 

104 NotImplementedError 

105 Raised if the selected translator does not support a required 

106 property. 

107 

108 Notes 

109 ----- 

110 Headers will be corrected if correction files are located and this will 

111 modify the header provided to the constructor. 

112 

113 Values of the properties are read-only. 

114 """ 

115 

116 # Static typing requires that we define the standard dynamic properties 

117 # statically. 

118 if TYPE_CHECKING: 118 ↛ 119line 118 didn't jump to line 119, because the condition on line 118 was never true

119 telescope: int 

120 instrument: str 

121 location: astropy.coordinates.EarthLocation 

122 exposure_id: int 

123 visit_id: int 

124 physical_filter: str 

125 datetime_begin: astropy.time.Time 

126 datetime_end: astropy.time.Time 

127 exposure_group: str 

128 exposure_time: astropy.units.Quantity 

129 dark_time: astropy.units.Quantity 

130 boresight_airmass: float 

131 boresight_rotation_angle: astropy.units.Quantity 

132 boresight_rotation_coord: str 

133 detector_num: int 

134 detector_name: str 

135 detector_serial: str 

136 detector_group: str 

137 detector_exposure_id: int 

138 object: str 

139 temperature: astropy.units.Quantity 

140 pressure: astropy.units.Quantity 

141 relative_humidity: float 

142 tracking_radec: astropy.coordinates.SkyCoord 

143 altaz_begin: astropy.coordinates.AltAz 

144 science_program: str 

145 observation_counter: int 

146 observation_reason: str 

147 observation_type: str 

148 observation_id: str 

149 observing_day: int 

150 group_counter_start: int 

151 group_counter_end: int 

152 has_simulated_content: bool 

153 

154 def __init__( 

155 self, 

156 header: Optional[MutableMapping[str, Any]], 

157 filename: Optional[str] = None, 

158 translator_class: Optional[Type[MetadataTranslator]] = None, 

159 pedantic: bool = False, 

160 search_path: Optional[Sequence[str]] = None, 

161 required: Optional[Set[str]] = None, 

162 subset: Optional[Set[str]] = None, 

163 ) -> None: 

164 

165 # Initialize the empty object 

166 self._header: MutableMapping[str, Any] = {} 

167 self.filename = filename 

168 self._translator = None 

169 self.translator_class_name = "<None>" 

170 

171 # To allow makeObservationInfo to work, we special case a None 

172 # header 

173 if header is None: 

174 return 

175 

176 # Fix up the header (if required) 

177 fix_header(header, translator_class=translator_class, filename=filename, search_path=search_path) 

178 

179 # Store the supplied header for later stripping 

180 self._header = header 

181 

182 if translator_class is None: 

183 translator_class = MetadataTranslator.determine_translator(header, filename=filename) 

184 elif not issubclass(translator_class, MetadataTranslator): 

185 raise TypeError(f"Translator class must be a MetadataTranslator, not {translator_class}") 

186 

187 self._declare_extensions(translator_class.extensions) 

188 

189 # Create an instance for this header 

190 translator = translator_class(header, filename=filename) 

191 

192 # Store the translator 

193 self._translator = translator 

194 self.translator_class_name = translator_class.__name__ 

195 

196 # Form file information string in case we need an error message 

197 if filename: 

198 file_info = f" and file {filename}" 

199 else: 

200 file_info = "" 

201 

202 # Determine the properties of interest 

203 full_set = set(self.all_properties) 

204 if subset is not None: 

205 if not subset: 

206 raise ValueError("Cannot request no properties be calculated.") 

207 if not subset.issubset(full_set): 

208 raise ValueError( 

209 "Requested subset is not a subset of known properties. " f"Got extra: {subset - full_set}" 

210 ) 

211 properties = subset 

212 else: 

213 properties = full_set 

214 

215 if required is None: 

216 required = set() 

217 else: 

218 if not required.issubset(full_set): 

219 raise ValueError("Requested required properties include unknowns: " f"{required - full_set}") 

220 

221 # Loop over each property and request the translated form 

222 for t in properties: 

223 # prototype code 

224 method = f"to_{t}" 

225 property = f"_{t}" if not t.startswith("ext_") else t 

226 

227 try: 

228 value = getattr(translator, method)() 

229 except NotImplementedError as e: 

230 raise NotImplementedError( 

231 f"No translation exists for property '{t}'" f" using translator {translator.__class__}" 

232 ) from e 

233 except KeyError as e: 

234 err_msg = ( 

235 f"Error calculating property '{t}' using translator {translator.__class__}" f"{file_info}" 

236 ) 

237 if pedantic or t in required: 

238 raise KeyError(err_msg) from e 

239 else: 

240 log.debug("Calculation of property '%s' failed with header: %s", t, header) 

241 log.warning(f"Ignoring {err_msg}: {e}") 

242 continue 

243 

244 definition = self.all_properties[t] 

245 if not self._is_property_ok(definition, value): 

246 err_msg = ( 

247 f"Value calculated for property '{t}' is wrong type " 

248 f"({type(value)} != {definition.str_type}) using translator {translator.__class__}" 

249 f"{file_info}" 

250 ) 

251 if pedantic or t in required: 

252 raise TypeError(err_msg) 

253 else: 

254 log.debug("Calcuation of property '%s' had unexpected type with header: %s", t, header) 

255 log.warning(f"Ignoring {err_msg}") 

256 

257 if value is None and t in required: 

258 raise KeyError(f"Calculation of required property {t} resulted in a value of None") 

259 

260 super().__setattr__(property, value) # allows setting even write-protected extensions 

261 

262 @staticmethod 

263 def _get_all_properties( 

264 extensions: Optional[Dict[str, PropertyDefinition]] = None 

265 ) -> Dict[str, PropertyDefinition]: 

266 """Return the definitions of all properties 

267 

268 Parameters 

269 ---------- 

270 extensions : `dict` [`str`: `PropertyDefinition`] 

271 List of extension property definitions, indexed by name (with no 

272 "ext_" prefix). 

273 

274 Returns 

275 ------- 

276 properties : `dict` [`str`: `PropertyDefinition`] 

277 Merged list of all property definitions, indexed by name. Extension 

278 properties will be listed with an ``ext_`` prefix. 

279 """ 

280 properties = dict(PROPERTIES) 

281 if extensions: 

282 properties.update({"ext_" + pp: dd for pp, dd in extensions.items()}) 

283 return properties 

284 

285 def _declare_extensions(self, extensions: Optional[Dict[str, PropertyDefinition]]) -> None: 

286 """Declare and set up extension properties 

287 

288 This should always be called internally as part of the creation of a 

289 new `ObservationInfo`. 

290 

291 The core set of properties each have a python ``property`` that makes 

292 them read-only, and serves as a useful place to hang the docstring. 

293 However, the core set are set up at compile time, whereas the extension 

294 properties have to be configured at run time (because we don't know 

295 what they will be until we look at the header and figure out what 

296 instrument we're dealing with) when we have an instance rather than a 

297 class (and python ``property`` doesn't work on instances; only on 

298 classes). We therefore use a separate scheme for the extension 

299 properties: we write them directly to their associated instance 

300 variable, and we use ``__setattr__`` to protect them as read-only. 

301 Unfortunately, with this scheme, we can't give extension properties a 

302 docstring; but we're setting them up at runtime, so maybe that's not 

303 terribly important. 

304 

305 Parameters 

306 ---------- 

307 extensions : `dict` [`str`: `PropertyDefinition`] 

308 List of extension property definitions, indexed by name (with no 

309 "ext_" prefix). 

310 """ 

311 if not extensions: 

312 extensions = {} 

313 for name in extensions: 

314 super().__setattr__("ext_" + name, None) 

315 self.extensions = extensions 

316 self.all_properties = self._get_all_properties(extensions) 

317 

318 def __setattr__(self, name: str, value: Any) -> Any: 

319 """Set attribute 

320 

321 This provides read-only protection for the extension properties. The 

322 core set of properties have read-only protection via the use of the 

323 python ``property``. 

324 """ 

325 if hasattr(self, "extensions") and name.startswith("ext_") and name[4:] in self.extensions: 

326 raise AttributeError(f"Attribute {name} is read-only") 

327 return super().__setattr__(name, value) 

328 

329 @classmethod 

330 def _is_property_ok(cls, definition: PropertyDefinition, value: Any) -> bool: 

331 """Compare the supplied value against the expected type as defined 

332 for the corresponding property. 

333 

334 Parameters 

335 ---------- 

336 definition : `PropertyDefinition` 

337 Property definition. 

338 value : `object` 

339 Value of the property to validate. 

340 

341 Returns 

342 ------- 

343 is_ok : `bool` 

344 `True` if the value is of an appropriate type. 

345 

346 Notes 

347 ----- 

348 Currently only the type of the property is validated. There is no 

349 attempt to check bounds or determine that a Quantity is compatible 

350 with the property. 

351 """ 

352 if value is None: 

353 return True 

354 

355 # For AltAz coordinates, they can either arrive as AltAz or 

356 # as SkyCoord(frame=AltAz) so try to find the frame inside 

357 # the SkyCoord. 

358 if issubclass(definition.py_type, AltAz) and isinstance(value, SkyCoord): 

359 value = value.frame 

360 

361 if not isinstance(value, definition.py_type): 

362 return False 

363 

364 return True 

365 

366 @property 

367 def cards_used(self) -> FrozenSet[str]: 

368 """Header cards used for the translation. 

369 

370 Returns 

371 ------- 

372 used : `frozenset` of `str` 

373 Set of card used. 

374 """ 

375 if not self._translator: 

376 return frozenset() 

377 return self._translator.cards_used() 

378 

379 def stripped_header(self) -> MutableMapping[str, Any]: 

380 """Return a copy of the supplied header with used keywords removed. 

381 

382 Returns 

383 ------- 

384 stripped : `dict`-like 

385 Same class as header supplied to constructor, but with the 

386 headers used to calculate the generic information removed. 

387 """ 

388 hdr = copy.copy(self._header) 

389 used = self.cards_used 

390 for c in used: 

391 del hdr[c] 

392 return hdr 

393 

394 def __str__(self) -> str: 

395 # Put more interesting answers at front of list 

396 # and then do remainder 

397 priority = ("instrument", "telescope", "datetime_begin") 

398 properties = sorted(set(self.all_properties) - set(priority)) 

399 

400 result = "" 

401 for p in itertools.chain(priority, properties): 

402 value = getattr(self, p) 

403 if isinstance(value, astropy.time.Time): 

404 value.format = "isot" 

405 value = str(value.value) 

406 result += f"{p}: {value}\n" 

407 

408 return result 

409 

410 def __eq__(self, other: Any) -> bool: 

411 """Compares equal if standard properties are equal""" 

412 if not isinstance(other, ObservationInfo): 

413 return NotImplemented 

414 

415 # Compare simplified forms. 

416 # Cannot compare directly because nan will not equate as equal 

417 # whereas they should be equal for our purposes 

418 self_simple = self.to_simple() 

419 other_simple = other.to_simple() 

420 

421 # We don't care about the translator internal detail 

422 self_simple.pop("_translator", None) 

423 other_simple.pop("_translator", None) 

424 

425 for k, self_value in self_simple.items(): 

426 other_value = other_simple[k] 

427 if self_value != other_value: 

428 if math.isnan(self_value) and math.isnan(other_value): 

429 # If both are nan this is fine 

430 continue 

431 return False 

432 return True 

433 

434 def __lt__(self, other: Any) -> bool: 

435 if not isinstance(other, ObservationInfo): 

436 return NotImplemented 

437 return self.datetime_begin < other.datetime_begin 

438 

439 def __gt__(self, other: Any) -> bool: 

440 if not isinstance(other, ObservationInfo): 

441 return NotImplemented 

442 return self.datetime_begin > other.datetime_begin 

443 

444 def __getstate__(self) -> Tuple[Any, ...]: 

445 """Get pickleable state 

446 

447 Returns the properties. Deliberately does not preserve the full 

448 current state; in particular, does not return the full header or 

449 translator. 

450 

451 Returns 

452 ------- 

453 state : `tuple` 

454 Pickled state. 

455 """ 

456 state = dict() 

457 for p in self.all_properties: 

458 state[p] = getattr(self, p) 

459 

460 return state, self.extensions 

461 

462 def __setstate__(self, state: Tuple[Any, ...]) -> None: 

463 """Set object state from pickle 

464 

465 Parameters 

466 ---------- 

467 state : `tuple` 

468 Pickled state. 

469 """ 

470 try: 

471 state, extensions = state 

472 except ValueError: 

473 # Backwards compatibility for pickles generated before DM-34175 

474 extensions = {} 

475 self._declare_extensions(extensions) 

476 for p in self.all_properties: 

477 if p.startswith("ext_"): 

478 # allows setting even write-protected extensions 

479 super().__setattr__(p, state[p]) # type: ignore 

480 else: 

481 property = f"_{p}" 

482 setattr(self, property, state[p]) # type: ignore 

483 

484 def to_simple(self) -> MutableMapping[str, Any]: 

485 """Convert the contents of this object to simple dict form. 

486 

487 The keys of the dict are the standard properties but the values 

488 can be simplified to support JSON serialization. For example a 

489 SkyCoord might be represented as an ICRS RA/Dec tuple rather than 

490 a full SkyCoord representation. 

491 

492 Any properties with `None` value will be skipped. 

493 

494 Can be converted back to an `ObservationInfo` using `from_simple()`. 

495 

496 Returns 

497 ------- 

498 simple : `dict` of [`str`, `Any`] 

499 Simple dict of all properties. 

500 

501 Notes 

502 ----- 

503 Round-tripping of extension properties requires that the 

504 `ObservationInfo` was created with the help of a registered 

505 `MetadataTranslator` (which contains the extension property 

506 definitions). 

507 """ 

508 simple = {} 

509 if hasattr(self, "_translator") and self._translator and self._translator.name: 

510 simple["_translator"] = self._translator.name 

511 

512 for p in self.all_properties: 

513 property = f"_{p}" if not p.startswith("ext_") else p 

514 value = getattr(self, property) 

515 if value is None: 

516 continue 

517 

518 # Access the function to simplify the property 

519 simplifier = self.all_properties[p].to_simple 

520 

521 if simplifier is None: 

522 simple[p] = value 

523 continue 

524 

525 simple[p] = simplifier(value) 

526 

527 return simple 

528 

529 def to_json(self) -> str: 

530 """Serialize the object to JSON string. 

531 

532 Returns 

533 ------- 

534 j : `str` 

535 The properties of the ObservationInfo in JSON string form. 

536 

537 Notes 

538 ----- 

539 Round-tripping of extension properties requires that the 

540 `ObservationInfo` was created with the help of a registered 

541 `MetadataTranslator` (which contains the extension property 

542 definitions). 

543 """ 

544 return json.dumps(self.to_simple()) 

545 

546 @classmethod 

547 def from_simple(cls, simple: MutableMapping[str, Any]) -> ObservationInfo: 

548 """Convert the entity returned by `to_simple` back into an 

549 `ObservationInfo`. 

550 

551 Parameters 

552 ---------- 

553 simple : `dict` [`str`, `Any`] 

554 The dict returned by `to_simple()` 

555 

556 Returns 

557 ------- 

558 obsinfo : `ObservationInfo` 

559 New object constructed from the dict. 

560 

561 Notes 

562 ----- 

563 Round-tripping of extension properties requires that the 

564 `ObservationInfo` was created with the help of a registered 

565 `MetadataTranslator` (which contains the extension property 

566 definitions). 

567 """ 

568 extensions = {} 

569 translator = simple.pop("_translator", None) 

570 if translator: 

571 if translator not in MetadataTranslator.translators: 

572 raise KeyError(f"Unrecognised translator: {translator}") 

573 extensions = MetadataTranslator.translators[translator].extensions 

574 

575 properties = cls._get_all_properties(extensions) 

576 

577 processed: Dict[str, Any] = {} 

578 for k, v in simple.items(): 

579 

580 if v is None: 

581 continue 

582 

583 # Access the function to convert from simple form 

584 complexifier = properties[k].from_simple 

585 

586 if complexifier is not None: 

587 v = complexifier(v, **processed) 

588 

589 processed[k] = v 

590 

591 return cls.makeObservationInfo(extensions=extensions, **processed) 

592 

593 @classmethod 

594 def from_json(cls, json_str: str) -> ObservationInfo: 

595 """Create `ObservationInfo` from JSON string. 

596 

597 Parameters 

598 ---------- 

599 json_str : `str` 

600 The JSON representation. 

601 

602 Returns 

603 ------- 

604 obsinfo : `ObservationInfo` 

605 Reconstructed object. 

606 

607 Notes 

608 ----- 

609 Round-tripping of extension properties requires that the 

610 `ObservationInfo` was created with the help of a registered 

611 `MetadataTranslator` (which contains the extension property 

612 definitions). 

613 """ 

614 simple = json.loads(json_str) 

615 return cls.from_simple(simple) 

616 

617 @classmethod 

618 def makeObservationInfo( # noqa: N802 

619 cls, *, extensions: Optional[Dict[str, PropertyDefinition]] = None, **kwargs: Any 

620 ) -> ObservationInfo: 

621 """Construct an `ObservationInfo` from the supplied parameters. 

622 

623 Parameters 

624 ---------- 

625 extensions : `dict` [`str`: `PropertyDefinition`], optional 

626 Optional extension definitions, indexed by extension name (without 

627 the ``ext_`` prefix, which will be added by `ObservationInfo`). 

628 **kwargs 

629 Name-value pairs for any properties to be set. In the case of 

630 extension properties, the names should include the ``ext_`` prefix. 

631 

632 Notes 

633 ----- 

634 The supplied parameters should use names matching the property. 

635 The type of the supplied value will be checked against the property. 

636 Any properties not supplied will be assigned a value of `None`. 

637 

638 Raises 

639 ------ 

640 KeyError 

641 Raised if a supplied parameter key is not a known property. 

642 TypeError 

643 Raised if a supplied value does not match the expected type 

644 of the property. 

645 """ 

646 

647 obsinfo = cls(None) 

648 obsinfo._declare_extensions(extensions) 

649 

650 unused = set(kwargs) 

651 

652 for p in obsinfo.all_properties: 

653 if p in kwargs: 

654 property = f"_{p}" if not p.startswith("ext_") else p 

655 value = kwargs[p] 

656 definition = obsinfo.all_properties[p] 

657 if not cls._is_property_ok(definition, value): 

658 raise TypeError( 

659 f"Supplied value {value} for property {p} " 

660 f"should be of class {definition.str_type} not {value.__class__}" 

661 ) 

662 super(cls, obsinfo).__setattr__(property, value) # allows setting write-protected extensions 

663 unused.remove(p) 

664 

665 # Recent additions to ObservationInfo may not be present in 

666 # serializations. In theory they can be derived from other 

667 # values in the default case. This might not be the right thing 

668 # to do. 

669 for k in ("group_counter_start", "group_counter_end"): 

670 if k not in kwargs and "observation_counter" in kwargs: 

671 super(cls, obsinfo).__setattr__(f"_{k}", obsinfo.observation_counter) 

672 if (k := "has_simulated_content") not in kwargs: 

673 super(cls, obsinfo).__setattr__(f"_{k}", False) 

674 

675 if unused: 

676 n = len(unused) 

677 raise KeyError(f"Unrecognized propert{'y' if n == 1 else 'ies'} provided: {', '.join(unused)}") 

678 

679 return obsinfo 

680 

681 

682# Method to add the standard properties 

683def _make_property(property: str, doc: str, return_typedoc: str, return_type: Type) -> Callable: 

684 """Create a getter method with associated docstring. 

685 

686 Parameters 

687 ---------- 

688 property : `str` 

689 Name of the property getter to be created. 

690 doc : `str` 

691 Description of this property. 

692 return_typedoc : `str` 

693 Type string of this property (used in the doc string). 

694 return_type : `class` 

695 Type of this property. 

696 

697 Returns 

698 ------- 

699 p : `function` 

700 Getter method for this property. 

701 """ 

702 

703 def getter(self: ObservationInfo) -> Any: 

704 return getattr(self, f"_{property}") 

705 

706 getter.__doc__ = f"""{doc} 

707 

708 Returns 

709 ------- 

710 {property} : `{return_typedoc}` 

711 Access the property. 

712 """ 

713 return getter 

714 

715 

716# Set up the core set of properties 

717# In order to provide read-only protection, each attribute is hidden behind a 

718# python "property" wrapper. 

719for name, definition in PROPERTIES.items(): 

720 setattr(ObservationInfo, f"_{name}", None) 

721 setattr( 

722 ObservationInfo, 

723 name, 

724 property(_make_property(name, definition.doc, definition.str_type, definition.py_type)), 

725 ) 

726 

727 

728def makeObservationInfo( # noqa: N802 

729 *, extensions: Optional[Dict[str, PropertyDefinition]] = None, **kwargs: Any 

730) -> ObservationInfo: 

731 """Construct an `ObservationInfo` from the supplied parameters. 

732 

733 Parameters 

734 ---------- 

735 extensions : `dict` [`str`: `PropertyDefinition`], optional 

736 Optional extension definitions, indexed by extension name (without 

737 the ``ext_`` prefix, which will be added by `ObservationInfo`). 

738 **kwargs 

739 Name-value pairs for any properties to be set. In the case of 

740 extension properties, the names should include the ``ext_`` prefix. 

741 

742 Notes 

743 ----- 

744 The supplied parameters should use names matching the property. 

745 The type of the supplied value will be checked against the property. 

746 Any properties not supplied will be assigned a value of `None`. 

747 

748 Raises 

749 ------ 

750 KeyError 

751 Raised if a supplied parameter key is not a known property. 

752 TypeError 

753 Raised if a supplied value does not match the expected type 

754 of the property. 

755 """ 

756 return ObservationInfo.makeObservationInfo(extensions=extensions, **kwargs)