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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 RunPlaybookOnHost(playbook_path, host, private_key, extra_vars=None):
 """ Runs the playbook and returns True if it completes successfully on a single host. """

  return RunPlaybookOnHosts(playbook_path, [host], private_key, extra_vars)