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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 pixels_from_coordinates(lat, lon, max_y, max_x):
 """ Return the 2 matrix with lat and lon of each pixel. Keyword arguments: lat -- A latitude matrix lon -- A longitude matrix max_y -- The max vertical pixels amount of an orthorectified image. max_x -- The max horizontal pixels amount of an orthorectified image. """

    # The degrees by pixel of the orthorectified image.
    x_ratio, y_ratio = max_x/360., max_y/180.
    x, y = np.zeros(lon.shape), np.zeros(lat.shape)
    x = (lon + 180.) * x_ratio
    y = (lat + 90.) * y_ratio
    return x, y