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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 update_defaults(self, prop_value_dict):
 """ Updates the value of one or more visual properties. :param prop_value_dict: Dictionary containing, for each visual property, the new value to use. """


        body = []
        for key in prop_value_dict:
            entry = {
                'visualProperty': key,
                'value': prop_value_dict[key]
            }
            body.append(entry)

        url = self.__url + 'defaults'
        requests.put(url, data=json.dumps(body), headers=HEADERS)