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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 load(self, url, offset, length):
 """ Load a file-like reader over http using range requests and an optional cookie created via a cookie_maker """

        headers = {}
        if offset != 0 or length != -1:
            headers['Range'] = BlockLoader._make_range_header(offset, length)

        if self.cookie_maker:
            if isinstance(self.cookie_maker, six.string_types):
                headers['Cookie'] = self.cookie_maker
            else:
                headers['Cookie'] = self.cookie_maker.make()

        if not self.session:
            self.session = requests.Session()

        r = self.session.get(url, headers=headers, stream=True)
        r.raise_for_status()
        return r.raw