E-mail prompt for send figure by mail does not work in py37_prep

[sshiraiwa]

Traceback (most recent call last): File "/Users/shiraiwa/src/piScope/python/ifigure/widgets/canvas/ifigure_canvas.py", line 3386, in mail_pic po.send_file(fname, parent=self.GetTopLevelParent()) File "/Users/shiraiwa/src/piScope/python/ifigure/utils/postoffice.py", line 130, in send_file self.ask_passwd(parent=parent) File "/Users/shiraiwa/src/piScope/python/ifigure/utils/postoffice.py", line 52, in ask_passwd self.passwd = binascii.b2a_hex(p_dlg.result[1]) TypeError: a bytes-like object is required, not 'str'