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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 pfm_to_pwm(self, pfm, pseudo=0.001):
 """Convert PFM with counts to a PFM with fractions. Parameters pfm : list 2-dimensional list with counts. pseudo : float Pseudocount used in conversion. Returns ------- pwm : list 2-dimensional list with fractions. """

        return [[(x + pseudo)/(float(np.sum(row)) + pseudo * 4) for x in row] for row in pfm]