input: Write a function to optimize the processing of a 2d array and store the transpose output in a new array.
  def transpose(A):
   n = len(A)
   m = len(A[0])
  
   B = [[0 for x in range(n)] for x in range(m)]
  
   for i in range(n):
   for j in range(m):
   B[j][i] = A[i][j]
  
   return B
   
  assert transpose([[1,2,3],[4,5,6]])==[[1,4],[2,5],[3,6]]
  assert transpose([[1,2],[3,4],[5,6]])==[[1,3,5],[2,4,6]]
  assert transpose([[1]])==[[1]]
  assert transpose([[1,2],[3,4]])==[[1,3],[2,4]]
  assert transpose([[]])==[[]]
output: def transpose(A):
      n = len(A)
      m = len(A[0]) if A else 0
      B = [[0 for _ in range(n)] for _ in range(m)]
      for i in range(n):
          for j in range(m):
              B[j][i] = A[i][j]
      return B