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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 get_ps(self, field_name, wait_pstate=True):
 """Get property from PersonaState `See full list of available fields_names <https://github.com/ValvePython/steam/blob/fa8a5127e9bb23185483930da0b6ae85e93055a7/protobufs/steammessages_clientserver_friends.proto#L125-L153>`_ """

        if not wait_pstate or self._pstate_ready.wait(timeout=5):
            if self._pstate is None and wait_pstate:
                self._steam.request_persona_state([self.steam_id])
                self._pstate_ready.wait(timeout=5)

            return getattr(self._pstate, field_name)
        return None