data = [('male', 'Homer', 'Simpson'), ('female', 'Marge', 'Simpson'), ('male', 'Bart', 'Simpson'),('female', 'Lisa', 'Simpson'),('infant', 'Maggie', 'Simpson')]
people = pd.DataFrame(data, columns=["gender", "first_name", "last_name"])

gender first_name last_name
0    male      Homer   Simpson
1  female      Marge   Simpson
2    male       Bart   Simpson
3  female       Lisa   Simpson
4  infant     Maggie   Simpson

def get_address(gender, first, last):
    title=""
    if gender=='male':
        title='Mr'
    elif gender=='female':
        title='Ms'

    if title=='':
        return first + ' '+ last
    else:
        return title + ' ' + first[0] + '. ' + last

people['address'] = map(lambda row: get_address(*row),people.get_values())



   gender first_name last_name         address
0    male      Homer   Simpson   Mr H. Simpson
1  female      Marge   Simpson   Ms M. Simpson
2    male       Bart   Simpson   Mr B. Simpson
3  female       Lisa   Simpson   Ms L. Simpson
4  infant     Maggie   Simpson  Maggie Simpson