new_contents: """
  Reverse bits of a given 32 bits unsigned integer.
  
  For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), 
  return 964176192 (represented in binary as 00111001011110000010100101000000).
  """
  
  class Solution(object):
      def reverseBits(self, n):
          """
          :type n: int
          :rtype: int
          """
          bin32=lambda x:bin(x)[2:].zfill(32)
          reverse=list(bin32(n))[::-1]
          return int(''.join(reverse),base=2)
  
subject: Create LeetCode-ReverseBits.py