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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 parse_doc(f, ctx=None, overwrite=False):
 """ Accepts an open file or a list of lines. """

    lg = LineGetter(f, comment_marker=("#", ";"), strip=False)
    cfg = ConfigParser(ctx).parse_doc(lg)
    set_defaults(cfg)
    if overwrite:
        squash(cfg)
    return cfg