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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 draw_feature_layer(self, surf, feature):
 """Draw a feature layer."""

    layer = feature.unpack(self._obs.observation)
    if layer is not None:
      surf.blit_np_array(feature.color(layer))
    else:  # Ignore layers that aren't in this version of SC2.
      surf.surf.fill(colors.black)