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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 add_param(self, group=None, type_='', field='', description=''):
 """parse and append a param"""

        group = group or '(Parameter)'
        group = group.lower()[1:-1]
        p = Param(type_, field, description)
        self.params[group][p.field] = p