Create a 20 char passphrase with easily typeable chars.

def GeneratePassphrase(length=20):
  """Create a 20 char passphrase with easily typeable chars."""
  valid_chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
  valid_chars += "0123456789 ,-_&$#"
  return "".join(random.choice(valid_chars) for i in range(length))