class_docstr: Returns a discrete Fourier transform matrix. The matrix is scaled
  with :math:`\frac{1}{\sqrt{n}}` so that it is unitary.
  
  Parameters
  ==========
  
  n : integer or Symbol
      Size of the transform.
  
  Examples
  ========
  
  >>> from sympy.abc import n
  >>> from sympy.matrices.expressions.fourier import DFT
  >>> DFT(3)
  DFT(3)
  >>> DFT(3).as_explicit()
  Matrix([
  [sqrt(3)/3,                sqrt(3)/3,                sqrt(3)/3],
  [sqrt(3)/3, sqrt(3)*exp(-2*I*pi/3)/3,  sqrt(3)*exp(2*I*pi/3)/3],
  [sqrt(3)/3,  sqrt(3)*exp(2*I*pi/3)/3, sqrt(3)*exp(-2*I*pi/3)/3]])
  >>> DFT(n).shape
  (n, n)
  
  References
  ==========
  
  .. [1] https://en.wikipedia.org/wiki/DFT_matrix
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code: def _eval_inverse(self):
      return IDFT(self.n)
  
file_path: sympy/sympy/matrices/expressions/fourier.py
imports: from sympy.core.sympify import _sympify
  from sympy.matrices.expressions import MatrixExpr
  from sympy.core.numbers import I
  from sympy.core.singleton import S
  from sympy.functions.elementary.exponential import exp
  from sympy.functions.elementary.miscellaneous import sqrt
label_desc: Use image node_id 3 for calling the DFT obj's underlying member method code with example usage: obj._eval_inverse() and returns: IDFT