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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 fetch(self):
 """ Retrieve updated data about the command from the server. @return: A new ApiCommand object. """

    if self.id == ApiCommand.SYNCHRONOUS_COMMAND_ID:
      return self

    resp = self._get_resource_root().get(self._path())
    return ApiCommand.from_json_dict(resp, self._get_resource_root())