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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 NewDefaultAgency(self, **kwargs):
 """Create a new Agency object and make it the default agency for this Schedule"""

    agency = self._gtfs_factory.Agency(**kwargs)
    if not agency.agency_id:
      agency.agency_id = util.FindUniqueId(self._agencies)
    self._default_agency = agency
    self.SetDefaultAgency(agency, validate=False)  # Blank agency won't validate
    return agency