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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_waveform_end_frequency(template=None, **kwargs):
 """Return the stop frequency of a template """

    input_params = props(template,**kwargs)
    approximant = kwargs['approximant']

    if approximant in _filter_ends:
        return _filter_ends[approximant](**input_params)
    else:
        return None