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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 fmt_ces(c, title=None):
 """Format a |CauseEffectStructure|."""

    if not c:
        return '()\n'

    if title is None:
        title = 'Cause-effect structure'

    concepts = '\n'.join(margin(x) for x in c) + '\n'
    title = '{} ({} concept{})'.format(
        title, len(c), '' if len(c) == 1 else 's')

    return header(title, concepts, HEADER_BAR_1, HEADER_BAR_1)