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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_fetch_headers(self, method, headers):
 """merge class headers with passed in headers :param method: string, (eg, GET or POST), this is passed in so you can customize headers based on the method that you are calling :param headers: dict, all the headers passed into the fetch method :returns: passed in headers merged with global class headers """

        all_headers = self.headers.copy()
        if headers:
            all_headers.update(headers)
        return Headers(all_headers)