Find all data references for a partial data ID.
Parameters
----------
butler: `lsst.daf.persistence.Butler`
The repository to query for data.
datasetType : `str`
The type of data references to return.
level : `str`
The level of data ID at which to search. If the empty string, the
default level for ``datasetType`` shall be used.
dataId : `lsst.daf.persistence.DataRef`, or `dict` from `str` to any
Butler identifier naming the data to be retrieved. If ommitted, an
unrestricted data ID shall be used.
Returns
-------
dataRefs : iterable of `lsst.daf.persistence.ButlerDataRef`
Complete data references matching ``dataId``. Only references to
existing data shall be returned.
Definition at line 29 of file butlerHelpers.py.