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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 bunkers_storm_motion(pressure, u, v, heights):
 r"""Calculate the Bunkers right-mover and left-mover storm motions and sfc-6km mean flow. Uses the storm motion calculation from [Bunkers2000]_. Parameters pressure : array-like Pressure from sounding u : array-like U component of the wind v : array-like V component of the wind heights : array-like Heights from sounding Returns ------- right_mover: `pint.Quantity` U and v component of Bunkers RM storm motion left_mover: `pint.Quantity` U and v component of Bunkers LM storm motion wind_mean: `pint.Quantity` U and v component of sfc-6km mean flow """

    # mean wind from sfc-6km
    wind_mean = concatenate(mean_pressure_weighted(pressure, u, v, heights=heights,
                                                   depth=6000 * units('meter')))

    # mean wind from sfc-500m
    wind_500m = concatenate(mean_pressure_weighted(pressure, u, v, heights=heights,
                                                   depth=500 * units('meter')))

    # mean wind from 5.5-6km
    wind_5500m = concatenate(mean_pressure_weighted(pressure, u, v, heights=heights,
                                                    depth=500 * units('meter'),
                                                    bottom=heights[0] + 5500 * units('meter')))

    # Calculate the shear vector from sfc-500m to 5.5-6km
    shear = wind_5500m - wind_500m

    # Take the cross product of the wind shear and k, and divide by the vector magnitude and
    # multiply by the deviaton empirically calculated in Bunkers (2000) (7.5 m/s)
    shear_cross = concatenate([shear[1], -shear[0]])
    rdev = shear_cross * (7.5 * units('m/s').to(u.units) / np.hypot(*shear))

    # Add the deviations to the layer average wind to get the RM motion
    right_mover = wind_mean + rdev

    # Subtract the deviations to get the LM motion
    left_mover = wind_mean - rdev

    return right_mover, left_mover, wind_mean