code: def randkey(bits, keyspace=string.ascii_letters + string.digits + '#/.',
              rng=None):
      
      return "".join(char for char in iter_random_chars(bits, keyspace, rng))
docs: Returns a cryptographically secure random key of desired @bits of
          entropy within @keyspace using :class:random.SystemRandom
  
          @bits: (#int) minimum bits of entropy
          @keyspace: (#str) or iterable allowed output chars
          @rng: the random number generator to use. Defaults to
              :class:random.SystemRandom. Must have a |choice| method
  
          -> (#str) random key
  
          ..
              from vital.security import randkey
  
              randkey(24)
              # -> '9qaX'
              randkey(48)
              # -> 'iPJ5YWs9'
              randkey(64)
              # - > 'C..VJ.KLdxg'
              randkey(64, keyspace="abc", rng=random)
              # -> 'aabcccbabcaacaccccabcaabbabcacabacbbbaaab'
          ..