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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 convert_hpdist(self, node):
 """ Convert the given node into a probability mass function for the hypo depth distribution. :param node: a hypoDepthDist node :returns: a :class:`openquake.hazardlib.pmf.PMF` instance """

        with context(self.fname, node):
            hcdist = [(hd['probability'], hd['depth'])
                      for hd in node.hypoDepthDist]
            if not self.spinning_floating:  # consider the first hypocenter
                hcdist = [(1, hcdist[0][1])]
            return pmf.PMF(hcdist)