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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 zip_ll_row(params, data_row):
 """ Returns the negative log-likelihood of a row given ZIP data. Args: params (list):
 [lambda zero-inf] data_row (array):
 1d array Returns: negative log-likelihood """

    l = params[0]
    pi = params[1]
    d0 = (data_row==0)
    likelihood = d0*pi + (1-pi)*poisson.pmf(data_row, l)
    return -np.log(likelihood+eps).sum()