def _delete_credential(self, key):
        """Delete a credential and write the multistore.

        This must be called when the multistore is locked.

        Args:
            key: The key used to retrieve the credential
        """
        try:
            del self._data[key]
        except __HOLE__:
            pass
        self._write()
dataset/ETHPy150Open google/oauth2client/oauth2client/contrib/multistore_file.py/_MultiStore._delete_credential