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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 kata2hira(text, ignore=''):
 """Convert Full-width Katakana to Hiragana Parameters text : str Full-width Katakana string. ignore : str Characters to be ignored in converting. Return ------ str Hiragana string. Examples -------- 巴まみ まみさン """

    if ignore:
        k2h_map = _exclude_ignorechar(ignore, K2H_TABLE.copy())
        return _convert(text, k2h_map)
    return _convert(text, K2H_TABLE)