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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 set_host_def(self, hostdef):
        '''
        Sets the hostdef param which will get passed to the Host Agent which
        the agency starts if it becomes the master.
        '''
        if self._hostdef is not None:
            self.info("Overwriting previous hostdef, which was %r",
                      self._hostdef)
        self._hostdef = hostdef