code: def colormapper(value, lower=0, upper=1, cmap=None):
      
  
      cmap = get_cmap(cmap)
      if upper - lower == 0:
          rgba = cmap(0)
      else:
          rgba = cmap((value - lower) / float(upper - lower))
      hex_ = rgb2hex(rgba)
      return hex_
docs: Maps values to colors by normalizing within [a,b], obtaining rgba from the
      given matplotlib color map for heatmap polygon coloring.
  
      Parameters
      ----------
      value: float
          The value to be colormapped
      lower: float
          Lower bound of colors
      upper: float
          Upper bound of colors
      cmap: String or matplotlib.colors.Colormap (optional)
          Colormap object to prevent repeated lookup
  
      Returns
      -------
      hex_, float
          The value mapped to an appropriate RGBA color value