code: def plot_di_sym(fignum, DIblock, sym):
      global globals
      
      X_down, X_up, Y_down, Y_up = [], [], [], []  # initialize some variables
      plt.figure(num=fignum)
  #
  #   plot the data - separate upper and lower hemispheres
  #
      for rec in DIblock:
          Up, Down = 0, 0
          XY = pmag.dimap(rec[0], rec[1])
          if rec[1] >= 0:
              X_down.append(XY[0])
              Y_down.append(XY[1])
          else:
              X_up.append(XY[0])
              Y_up.append(XY[1])
  #
      if 'size' not in list(sym.keys()):
          size = 50
      else:
          size = sym['size']
      if 'edgecolor' not in list(sym.keys()):
          sym['edgecolor'] = 'k'
      if len(X_down) > 0:
          plt.scatter(X_down, Y_down, marker=sym['lower'][0],
                      c=sym['lower'][1], s=size, edgecolor=sym['edgecolor'])
          if globals != 0:
              globals.DIlist = X_down
              globals.DIlisty = Y_down
      if len(X_up) > 0:
          plt.scatter(X_up, Y_up, marker=sym['upper'][0],
                      c=sym['upper'][1], s=size, edgecolor=sym['edgecolor'])
          if globals != 0:
              globals.DIlist = X_up
              globals.DIlisty = Y_up
docs: plots directions on equal area net
      Parameters
      _________
      fignum : matplotlib figure number
      DIblock : nested list of dec, inc pairs
      sym : set matplotlib symbol (e.g., 'bo' for blue circles)