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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 _encode_batched_write_command( namespace, operation, command, docs, check_keys, opts, ctx):
 """Encode the next batched insert, update, or delete command. """

    buf = StringIO()

    to_send, _ = _batched_write_command_impl(
        namespace, operation, command, docs, check_keys, opts, ctx, buf)
    return buf.getvalue(), to_send