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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 set_hash_key(self, file):
 """Calculate and store hash key for file."""

        filehasher = hashlib.md5()
        while True:
            data = file.read(8192)
            if not data:
                break
            filehasher.update(data)
        file.seek(0)
        self.hash_key = filehasher.hexdigest()