def b64decode(s, altchars=None):
    if altchars is not None:
        s = _translate(s, {altchars[0]: '+', altchars[1]: '/'})
    try:
        return binascii.a2b_base64(s)
    except binascii.Error, msg:
        # Transform this exception for consistency
        raise TypeError(msg)
Decode a Base64 encoded string.
dataset/ETHPy150Open anandology/pyjamas/pyjs/src/pyjs/lib/base64.py/b64decode