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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 build_params(self, params={}):
 """ build a params dictionary with current editId and packageName. use optional params parameter to merge additional params into resulting dictionary. """

        z = params.copy()
        z.update({'editId': self.edit_id, 'packageName': self.package_name})
        return z