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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_custom(self, params):
 """Adds new custom parameter after making sure it's of type dict. :param params: Dictionary containing one or more parameters """


        if isinstance(params, dict) is False:
            raise InvalidUsage("custom parameters must be of type `dict`")

        self._custom_params.update(params)