Encode bytes-like object b in base85 format and return a bytes object.
If wrapcol is non-zero, insert a newline (b'\n') character after at most
every wrapcol characters.
The input is padded with b' ' so its length is a multiple of 4
bytes before encoding. If pad is true, all the resulting
characters are retained in the output, which will always be a
multiple of 5 bytes.