imaplib.py 文件源码

def encode(self, inp):
        #
        #  Invoke binascii.b2a_base64 iteratively with
        #  short even length buffers, strip the trailing
        #  line feed from the result and append.  "Even"
        #  means a number that factors to both 6 and 8,
        #  so when it gets to the end of the 8-bit input
        #  there's no partial 6-bit output.
        #
        oup = ''
        while inp:
            if len(inp) > 48:
                t = inp[:48]
                inp = inp[48:]
            else:
                t = inp
                inp = ''
            e = binascii.b2a_base64(t)
            if e:
                oup = oup + e[:-1]
        return oup