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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_alt_description(self):
 """ Returns the alternate description of a parameter. Only pipeline prompt-when-run parameters can have alternate names and alternate descriptions """

        if 'altDescription' in self.attributes and bool(self.attributes['altDescription'].strip()):
            return self.attributes['altDescription']
        else:
            return None