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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 exvp(pos_x, pos_y):
 """Convert virtual pixel to real pixel"""

    pos_x = numpy.asarray(pos_x)
    pos_y = numpy.asarray(pos_y)
    # convert virtual pixel to real pixel
    # convert world coordinate to pixel
    center = [1024.5, 1024.5]
    cf  = EMIR_PLATESCALE_RADS
    pos_base_x = pos_x - center[0]
    pos_base_y = pos_y - center[1]
    ra = numpy.hypot(pos_base_x, pos_base_y)
    thet = numpy.arctan2(pos_base_y, pos_base_x)

    r  = cf * ra

    rr1 = 1 + 14606.7 * r**2 + 1739716115.1 * r**4

    nx1 = rr1 * ra * numpy.cos(thet) + center[0]
    ny1 = rr1 * ra * numpy.sin(thet) + center[1]
    return nx1, ny1