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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 correlation(a, b):
    "Returns correlation distance between a and b"
    if isinstance(a, list):
        a = np.array(a)
    if isinstance(b, list):
        b = np.array(b)
    a = a.reshape(1, -1)
    b = b.reshape(1, -1)
    return cdist(a, b, 'correlation')