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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_bool_default_value(property_name, default_value_string):
 """Parse and return the default value for a boolean property."""

    lowercased_value_string = default_value_string.lower()
    if lowercased_value_string in {'0', 'false'}:
        return False
    elif lowercased_value_string in {'1', 'true'}:
        return True
    else:
        raise AssertionError(u'Unsupported default value for boolean property "{}": '
                             u'{}'.format(property_name, default_value_string))