#!/usr/bin/env python3

from email.message import EmailMessage
from email.policy import SMTP
msg = EmailMessage(policy=SMTP)
msg['To'] = 'foo@bar.com'
msg['From'] = 'bar@foo.com'
msg['Reply-To'] = '"foo Research, Inc. Foofoo BarBar on Summer Special Friday: 0.50 days (2021-02-31)" <catchall@foobar.exchange.com>'
msg.set_content('Test')
print(msg.as_string())

# Result:
# To: foo@bar.com
# From: bar@foo.com
# Reply-To: foo Research, Inc. Foofoo BarBar on Summer Special Friday: 0.50 days
#  (2021-02-31) <catchall@foobar.exchange.com>
# Content-Type: text/plain; charset="utf-8"
# Content-Transfer-Encoding: 7bit
# MIME-Version: 1.0