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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 uncomment_lines(lines):
 """Uncomment the given list of lines and return them. The first hash mark following any amount of whitespace will be removed on each line."""

    ret = []
    for line in lines:
        ws_prefix, rest, ignore = RE_LINE_SPLITTER_UNCOMMENT.match(line).groups()
        ret.append(ws_prefix + rest)
    return ''.join(ret)