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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 moment(expr, order, central=False):
 """ Calculate the n-th order moment of the sequence :param expr: :param order: moment order, must be an integer :param central: if central moments are to be computed. :return: """

    if not isinstance(order, six.integer_types):
        raise ValueError('Only integer-ordered moments are supported.')
    if order < 0:
        raise ValueError('Only non-negative orders are supported.')
    output_type = _stats_type(expr)
    return _reduction(expr, Moment, output_type, _order=order, _center=central)