from datetime import datetime as dt
def suffix(d):
return 'th' if 11<=d<=13 else {1:'st',2:'nd',3:'rd'}.get(d%10, 'th')
def custom_strftime(format, t):
return t.strftime(format).replace('{S}', str(t.day) + suffix(t.day))
print custom_strftime('%B {S}, %Y', dt.now())