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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 _set_pseudotime(self):
 """Return pseudotime with respect to root point. """

        self.pseudotime = self.distances_dpt[self.iroot].copy()
        self.pseudotime /= np.max(self.pseudotime[self.pseudotime < np.inf])