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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 poisson_dist(p1, p2):
 """ Calculates the Poisson distance between two vectors. p1 can be a sparse matrix, while p2 has to be a dense matrix. """

    # ugh...
    p1_ = p1 + eps
    p2_ = p2 + eps
    return np.dot(p1_-p2_, np.log(p1_/p2_))