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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_xline(x, step):
 """Projection onto line in x"""

    if not np.isscalar(x):
        x= x[0]
    if x > 0.5:
        return np.array([0.5])
    else:
        return np.array([x])