docs: def fix_checksums(self, buff):
          """
            Fix a dex format buffer by setting all checksums
  
            :rtype: string
        """
          import zlib
          import hashlib
  
          signature = hashlib.sha1(buff[32:]).digest()
  
          buff = buff[:12] + signature + buff[32:]
          checksum = zlib.adler32(buff[12:])
          buff = buff[:8] + pack("=i", checksum) + buff[12:]
  
          debug("NEW SIGNATURE %s" % repr(signature))
          debug("NEW CHECKSUM %x" % checksum)
  
          return buff