Need help adding a sql List to a combo box PyQt5

[Alfalfa]

addItems takes a list, but you are passing a function instead. Try:

def pm_Combo(self):
        conn = sqlite3.connect('testdb.db')
        c = conn.cursor()
        c.execute("SELECT DISTINCT projectmanager FROM testtable2")
        pmList = c.fetchall()
        conn.commit()
        conn.close()
        return pmList

To make sure your variable is a list, you may verify the output of print(type(self.pm_Combo)) before the call to addItems.