code: def wavefunction(n, x):
      """
      Returns the wavefunction for particle on ring.
  
      Parameters
      ==========
  
      n : The quantum number.
          Here ``n`` can be positive as well as negative
          which can be used to describe the direction of motion of particle.
      x :
          The angle.
  
      Examples
      ========
  
      >>> from sympy.physics.pring import wavefunction
      >>> from sympy import Symbol, integrate, pi
      >>> x=Symbol("x")
      >>> wavefunction(1, x)
      sqrt(2)*exp(I*x)/(2*sqrt(pi))
      >>> wavefunction(2, x)
      sqrt(2)*exp(2*I*x)/(2*sqrt(pi))
      >>> wavefunction(3, x)
      sqrt(2)*exp(3*I*x)/(2*sqrt(pi))
  
      The normalization of the wavefunction is:
  
      >>> integrate(wavefunction(2, x)*wavefunction(-2, x), (x, 0, 2*pi))
      1
      >>> integrate(wavefunction(4, x)*wavefunction(-4, x), (x, 0, 2*pi))
      1
  
      References
      ==========
  
      .. [1] Atkins, Peter W.; Friedman, Ronald (2005). Molecular Quantum
             Mechanics (4th ed.).  Pages 71-73.
  
      """
      # sympify arguments
      n, x = S(n), S(x)
      return exp(n * I * x) / sqrt(2 * pi)
  
imports: from sympy.core.numbers import I, pi
  from sympy.core.singleton import S
  from sympy.functions.elementary.exponential import exp
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.physics.quantum.constants import hbar
label_desc: Use image node_id 1 for calling a global function with example usage: wavefunction(n, x) and returns: unknown