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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 reflection(n1, n2):
    '''
    Calculate the power reflection at the interface
    of two refractive index materials.

    Args:
        n1 (float): Refractive index of material 1.
        n2 (float): Refractive index of material 2.

    Returns:
        float: The percentage of reflected power.
    '''
    r = abs((n1-n2) / (n1+n2))**2
    return r