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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 effect_emd(d1, d2):
 """Compute the EMD between two effect repertoires. Because the nodes are independent, the EMD between effect repertoires is equal to the sum of the EMDs between the marginal distributions of each node, and the EMD between marginal distribution for a node is the absolute difference in the probabilities that the node is OFF. Args: d1 (np.ndarray):
 The first repertoire. d2 (np.ndarray):
 The second repertoire. Returns: float: The EMD between ``d1`` and ``d2``. """

    return sum(abs(marginal_zero(d1, i) - marginal_zero(d2, i))
               for i in range(d1.ndim))