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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 build_truncated_gr_mfd(mfd):
 """ Parses the truncated Gutenberg Richter MFD as a Node :param mfd: MFD as instance of :class: `openquake.hazardlib.mfd.truncated_gr.TruncatedGRMFD` :returns: Instance of :class:`openquake.baselib.node.Node` """

    return Node("truncGutenbergRichterMFD",
                {"aValue": mfd.a_val, "bValue": mfd.b_val,
                 "minMag": mfd.min_mag, "maxMag": mfd.max_mag})