Medford Brewing Company hosts its Second Wednesday Traditional Irish Session led by Shannon Heaton on flute. This evening she will be joined by Dan Accardi on accordion and Adam Hendey on guitar. They will play tunes in honor of Brian O’Donovan, the beloved host of “A Celtic Sojourn” on WGBH who passed away on October 6. Please note that this month’s session will start and end 30 minutes earlier than usual.