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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 AddService(self, new_service):
 """Add a new service to the list of ones we know about. Args: new_service (WindowsService):
 the service to add. """

    for service in self._services:
      if new_service == service:
        # If this service is the same as one we already know about, we
        # just want to add where it came from.
        service.sources.append(new_service.sources[0])
        return

    # We only add a new object to our list if we don't have
    # an identical one already.
    self._services.append(new_service)