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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 observer_position(time, lon, lat, alt):
 """Calculate observer ECI position. http://celestrak.com/columns/v02n03/ """


    lon = np.deg2rad(lon)
    lat = np.deg2rad(lat)

    theta = (gmst(time) + lon) % (2 * np.pi)
    c = 1 / np.sqrt(1 + F * (F - 2) * np.sin(lat)**2)
    sq = c * (1 - F)**2

    achcp = (A * c + alt) * np.cos(lat)
    x = achcp * np.cos(theta)  # kilometers
    y = achcp * np.sin(theta)
    z = (A * sq + alt) * np.sin(lat)

    vx = -MFACTOR * y  # kilometers/second
    vy = MFACTOR * x
    vz = 0

    return (x, y, z), (vx, vy, vz)