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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 _check_time_fn(self, time_instance=False):
 """ If time_fn is the global time function supplied by param.Dynamic.time_fn, make sure Dynamic parameters are using this time function to control their behaviour. If time_instance is True, time_fn must be a param.Time instance. """

        if time_instance and not isinstance(self.time_fn, param.Time):
            raise AssertionError("%s requires a Time object"
                                 % self.__class__.__name__)

        if self.time_dependent:
            global_timefn = self.time_fn is param.Dynamic.time_fn
            if global_timefn and not param.Dynamic.time_dependent:
                raise AssertionError("Cannot use Dynamic.time_fn as"
                                     " parameters are ignoring time.")