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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 _RunAndWaitForVFSFileUpdate(self, path):
 """Runs a flow on the client, and waits for it to finish."""


    client_id = rdf_client.GetClientURNFromPath(path)

    # If we're not actually in a directory on a client, no need to run a flow.
    if client_id is None:
      return

    flow_utils.UpdateVFSFileAndWait(
        client_id,
        token=self.token,
        vfs_file_urn=self.root.Add(path),
        timeout=self.timeout)