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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 _format_file_lines(files):
    '''Given a list of filenames that we're about to print, limit it to a
    reasonable number of lines.'''
    LINES_TO_SHOW = 10
    if len(files) <= LINES_TO_SHOW:
        lines = '\n'.join(files)
    else:
        lines = ('\n'.join(files[:LINES_TO_SHOW - 1]) + '\n...{} total'.format(
            len(files)))
    return lines