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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 make_params(self):
 """ Create all Variables to be returned later by get_params. By default this is a no-op. Models that need their fprop to be called for their params to be created can set `needs_dummy_fprop=True` in the constructor. """


    if self.needs_dummy_fprop:
      if hasattr(self, "_dummy_input"):
        return
      self._dummy_input = self.make_input_placeholder()
      self.fprop(self._dummy_input)