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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 hash_stream(self, url):
 # type: (str) -> str """Stream file from url and hash it using MD5. Must call setup method first. Args: url (str):
 URL to download Returns: str: MD5 hash of file """

        md5hash = hashlib.md5()
        try:
            for chunk in self.response.iter_content(chunk_size=10240):
                if chunk:  # filter out keep-alive new chunks
                    md5hash.update(chunk)
            return md5hash.hexdigest()
        except Exception as e:
            raisefrom(DownloadError, 'Download of %s failed in retrieval of stream!' % url, e)