def attach(self, filename=None, content=None, mimetype=None):
        if isinstance(filename, MIMEBase):
            assert content == mimetype == None
            self.attachments.append(filename)
        else:
            assert content is not None
            self.attachments.append((filename, content, mimetype))
Attaches a file with the given filename and content. The filename can
dataset/ETHPy150Open CollabQ/CollabQ/vendor/django/core/mail.py/EmailMessage.attach