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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 GetMetadata( self, metadata_key='', recursive=True, timeout=None, retry=True):
 """Retrieve the contents of metadata server for a metadata key. Args: metadata_key: string, the metadata key to watch for changes. recursive: bool, True if we should recursively watch for metadata changes. timeout: int, timeout in seconds for returning metadata output. retry: bool, True if we should retry on failure. Returns: json, the deserialized contents of the metadata server or None if error. """

    return self._HandleMetadataUpdate(
        metadata_key=metadata_key, recursive=recursive, wait=False,
        timeout=timeout, retry=retry)