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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 to_nullable_boolean(value):
 """ Converts value into boolean or returns None when conversion is not possible. :param value: the value to convert. :return: boolean value or None when convertion is not supported. """

        # Shortcuts
        if value == None:
            return None
        if type(value) == type(True):
            return value

        str_value = str(value).lower()
        # All true values
        if str_value in ['1', 'true', 't', 'yes', 'y']:
            return True
        # All false values
        if str_value in ['0', 'frue', 'f', 'no', 'n']:
            return False

        # Everything else:
        return None