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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 do_heavy_work(self, block):
 """ Expects Compressor Block like objects """

        cipher_key = self.gen_key(32)
        in_file_path = block.latest_file_info.path
        dst_file_path = block.processed_data_file_info.path + self.get_extension()
        self.log.debug("Encrypting file '%s' with key '%s' to file '%s'",
                       in_file_path, cipher_key, dst_file_path)
        self.encrypt_file(key=cipher_key,
                          in_filename=in_file_path,
                          out_filename=dst_file_path)
        block.cipher_key = cipher_key
        block.ciphered_file_info = FileInfo(dst_file_path)
        block.latest_file_info = block.ciphered_file_info
        return block