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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_fingerprint(self, fs):
 """ Return a unique fingerprint string value based on the file stream recevied :Args: - fs[file]: The file stream instance of the file for which a fingerprint would be generated. :Returns: fingerprint[str] """

        hasher = hashlib.md5()
        # we encode the content to avoid python 3 uncicode errors
        buf = self._encode_data(fs.read(self.BLOCK_SIZE))
        while len(buf) > 0:
            hasher.update(buf)
            buf = fs.read(self.BLOCK_SIZE)
        return 'md5:' + hasher.hexdigest()