code: def main():
      
      t, kf, t0, major, minor, prod, beta = sympy.symbols(
          't k_f t0 Y Z X beta', negative=False)
      for f in funcs:
          args = [t, kf, prod, major, minor]
          if f in (pseudo_rev, binary_rev):
              args.insert(2, kf/beta)
          expr = f(*args, backend='sympy')
          with open(f.__name__ + '.png', 'wb') as ofh:
              sympy.printing.preview(expr, output='png', filename='out.png',
                                     viewer='BytesIO', outputbuffer=ofh)
          with open(f.__name__ + '_diff.png', 'wb') as ofh:
              sympy.printing.preview(expr.diff(t).subs({t0: 0}).simplify(),
                                     output='png', filename='out.png',
                                     viewer='BytesIO', outputbuffer=ofh)
docs: This example demonstrates how to generate pretty equations from the analytic
      expressions found in ``chempy.kinetics.integrated``.