containment checking on DataQuery fails with KeyError

[gerritholl]

Describe the bug

Checking for containment in a DataQuery fails with KeyError.

To Reproduce

from satpy import DataQuery
dq = DataQuery(name="pytroll")
"name" in dq

Expected behavior

I expect either a TypeError (in case containment checking is not supported) or the answer (True/False).

Actual results

Traceback (most recent call last):
  File "/data/gholl/checkouts/protocode/mwe/dq-keyerror.py", line 3, in <module>
    "name" in dq
  File "/data/gholl/checkouts/satpy/satpy/dataset/dataid.py", line 512, in __getitem__
    return self._dict[key]
           ~~~~~~~~~~^^^^^
KeyError: 0

I don't understand where the 0 is coming from.

Environment Info:

• Satpy Version: main

Additional context

I want to test if a DataQuery contains a time parameter in my attempt of implementing temporal composites at #2495.

Workaround:

"name" in dq.to_dict()

[djhoese]

Yeah I guess it would make sense to have this functionality available and treat it as a "frozen dict".