code: def step(self, dt):
      for w in self.wheels:
          # Steer each wheel
          dir = np.sign(w.steer - w.joint.angle)
          val = abs(w.steer - w.joint.angle)
          w.joint.motorSpeed = dir * min(50.0 * val, 3.0)
  
          # Position => friction_limit
          grass = True
          friction_limit = (
              FRICTION_LIMIT * 0.6
          )  # Grass friction if no tile
          for tile in w.tiles:
              friction_limit = max(
                  friction_limit, FRICTION_LIMIT * tile.road_friction
              )
              grass = False
  
          # Force
          forw = w.GetWorldVector((0, 1))
          side = w.GetWorldVector((1, 0))
          v = w.linearVelocity
          vf = forw[0] * v[0] + forw[1] * v[1]  # forward speed
          vs = side[0] * v[0] + side[1] * v[1]  # side speed
  
          # WHEEL_MOMENT_OF_INERTIA*np.square(w.omega)/2 = E -- energy
          # WHEEL_MOMENT_OF_INERTIA*w.omega * domega/dt = dE/dt = W -- power
          # domega = dt*W/WHEEL_MOMENT_OF_INERTIA/w.omega
  
          # add small coef not to divide by zero
          w.omega += (
              dt
              * ENGINE_POWER
              * w.gas
              / WHEEL_MOMENT_OF_INERTIA
              / (abs(w.omega) + 5.0)
          )
          self.fuel_spent += dt * ENGINE_POWER * w.gas
  
          if w.brake >= 0.9:
              w.omega = 0
          elif w.brake > 0:
              BRAKE_FORCE = 15  # radians per second
              dir = -np.sign(w.omega)
              val = BRAKE_FORCE * w.brake
              if abs(val) > abs(w.omega):
                  val = abs(w.omega)  # low speed => same as = 0
              w.omega += dir * val
          w.phase += w.omega * dt
  
          vr = w.omega * w.wheel_rad  # rotating wheel speed
          f_force = (
              -vf + vr
          )  # force direction is direction of speed difference
          p_force = -vs
  
          # Physically correct is to always apply friction_limit until speed is equal.
          # But dt is finite, that will lead to oscillations if difference is already near zero.
  
          # Random coefficient to cut oscillations in few steps (have no effect on friction_limit)
          f_force *= 205000 * SIZE * SIZE
          p_force *= 205000 * SIZE * SIZE
          force = np.sqrt(np.square(f_force) + np.square(p_force))
  
          # Skid trace
          if abs(force) > 2.0 * friction_limit:
              if (
                  w.skid_particle
                  and w.skid_particle.grass == grass
                  and len(w.skid_particle.poly) < 30
              ):
                  w.skid_particle.poly.append(
                      (w.position[0], w.position[1])
                  )
              elif w.skid_start is None:
                  w.skid_start = w.position
              else:
                  w.skid_particle = self._create_particle(
                      w.skid_start, w.position, grass
                  )
                  w.skid_start = None
          else:
              w.skid_start = None
              w.skid_particle = None
  
          if abs(force) > friction_limit:
              f_force /= force
              p_force /= force
              force = friction_limit  # Correct physics here
              f_force *= force
              p_force *= force
  
          w.omega -= (
              dt * f_force * w.wheel_rad / WHEEL_MOMENT_OF_INERTIA
          )
  
          w.ApplyForceToCenter(
              (
                  p_force * side[0] + f_force * forw[0],
                  p_force * side[1] + f_force * forw[1],
              ),
              True,
          )
  
file_path: gym/gym/envs/box2d/car_dynamics.py
imports: import math
  import Box2D
  import numpy
  from gym.error import DependencyNotInstalled
label_desc: Use image node_id 5 for calling the Car obj's underlying member method code with example usage: obj.step(dt) without return types