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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 prox_yline(y, step):
 """Projection onto line in y"""

    if not np.isscalar(y):
        y= y[0]
    if y > -0.75:
        return np.array([-0.75])
    else:
        return np.array([y])