old_contents: from matexpr import MatrixExpr
  from sympy import Basic
  
  class Transpose(MatrixExpr):
      """Matrix Transpose
  
      Represents the transpose of a matrix expression.
  
      Use .T as shorthand
  
      >>> from sympy import MatrixSymbol, Transpose
      >>> A = MatrixSymbol('A', 3, 5)
      >>> B = MatrixSymbol('B', 5, 3)
      >>> Transpose(A)
      A'
      >>> A.T
      A'
      >>> Transpose(A*B)
      B'*A'
      """
      is_Transpose = True
      def __new__(cls, mat):
  
          if not mat.is_Matrix:
              return mat
  
          if hasattr(mat, '_eval_transpose'):
              return mat._eval_transpose()
  
          return Basic.__new__(cls, mat)
  
      @property
      def arg(self):
          return self.args[0]
  
      @property
      def shape(self):
          return self.arg.shape[::-1]
  
      def _entry(self, i, j):
          return self.arg._entry(j, i)
  
      def _eval_transpose(self):
          return self.arg
  
  from matmul import MatMul
  from matadd import MatAdd
  
new_contents: from matexpr import MatrixExpr
  from sympy import Basic
  
  class Transpose(MatrixExpr):
      """Matrix Transpose
  
      Represents the transpose of a matrix expression.
  
      Use .T as shorthand
  
      >>> from sympy import MatrixSymbol, Transpose
      >>> A = MatrixSymbol('A', 3, 5)
      >>> B = MatrixSymbol('B', 5, 3)
      >>> Transpose(A)
      A'
      >>> A.T
      A'
      >>> Transpose(A*B)
      B'*A'
      """
      is_Transpose = True
      def __new__(cls, mat):
  
          if not mat.is_Matrix:
              return mat
  
          if hasattr(mat, '_eval_transpose'):
              return mat._eval_transpose()
  
          return Basic.__new__(cls, mat)
  
      @property
      def arg(self):
          return self.args[0]
  
      @property
      def shape(self):
          return self.arg.shape[::-1]
  
      def _entry(self, i, j):
          return self.arg._entry(j, i)
  
      def _eval_transpose(self):
          return self.arg
  
subject: Remove unnecessary MatAdd and MatMul imports