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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 buffer_put_lines(buf, lines):
 """ Appends lines to a buffer. Parameters buf The buffer to write to lines The lines to append. """

    if any(isinstance(x, str) for x in lines):
        lines = [str(x) for x in lines]
    buf.write('\n'.join(lines))