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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_key(self, match_key, num_results=1, best=True, **dfilter):
 """Get multiple fully-specified keys that match the provided query. Args: key (DatasetID):
 DatasetID of query parameters to use for searching. Any parameter that is `None` is considered a wild card and any match is accepted. Can also be a string representing the dataset name or a number representing the dataset wavelength. num_results (int):
 Number of results to return. If `0` return all, if `1` return only that element, otherwise return a list of matching keys. **dfilter (dict):
 See `get_key` function for more information. """

        return get_key(match_key, self.keys(), num_results=num_results,
                       best=best, **dfilter)