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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 decode_dict(value_fields, client):
 """Converts a protobuf map of Firestore ``Value``-s. Args: value_fields (google.protobuf.pyext._message.MessageMapContainer):
 A protobuf map of Firestore ``Value``-s. client (~.firestore_v1beta1.client.Client):
 A client that has a document factory. Returns: Dict[str, Union[NoneType, bool, int, float, datetime.datetime, \ str, bytes, dict, ~google.cloud.Firestore.GeoPoint]]: A dictionary of native Python values converted from the ``value_fields``. """

    return {
        key: decode_value(value, client) for key, value in six.iteritems(value_fields)
    }