code: def __call__(self, value, clip=None):
      # I'm ignoring masked values and all kinds of edge cases to make a
      # simple example...
      x, y = [self.vmin, self.midpoint, self.vmax], [0, 0.5, 1]
      return np.ma.masked_array(np.interp(value, x, y))
  
imports: import matplotlib.pyplot
  import numpy
  import matplotlib.colors
label_desc: Use image node_id 2 for calling the MidpointNormalize obj's underlying member method code with example usage: obj.__call__(value, clip) and returns: np