begin parameters
  R0   100
  L0   500
  kon  0.01
  koff  0.1
end parameters

begin molecule types
 R(l)
 L(r)
end molecule types

begin seed species
  R(l)   R0    
  L(r)   L0
end seed species

begin reaction rules
   R(l) + L(r) <-> R(l!1).L(r!1) kon, koff
end reaction rules

begin observables
  Molecules R_total  R()
  Molecules L_total  L()
  Molecules L_unbound  L(r)
  Molecules R_unbound  R(l)
  Molecules L_bound  L(r!+)
  Molecules R_bound  R(l!+)
  Molecules R_complex_L  R().L()
  Molecules R_complex_L  R(l!1).L(r!1)
end observables

generate_network();
writeSBML();
simulate_ode({t_end=>50,n_steps=>20});