code: def __alfa_function(self, time, alfa, betta):
          
          
          return alfa * time * math.exp(-betta * time);
docs: !
          @brief Calculates value of alfa-function for difference between spike generation time and current simulation time.
          
          @param[in] time (double): Difference between last spike generation time and current time.
          @param[in] alfa (double): Alfa parameter for alfa-function.
          @param[in] betta (double): Betta parameter for alfa-function.
          
          @return (double) Value of alfa-function.