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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 is_true(key, default=False):
 """ Check if the value is in TRUE_VALUES """

    value = get(key, default)
    if isinstance(value, list):
        value = value[0]
    if isinstance(value, bool):
        return value
    if value is default:
        return default
    return value.lower() in TRUE_VALUES