Peanuts by Charles Schulz for April 09, 1963
Transcript:
Lucy shouts, "You blockhead! You struck out!" Charlie Brown drags his bat behind him and says, "I couldn't help it!"<BR><BR> Charlie Brown swings and says, "I really tried to clobber one!"<BR><BR> Lucy says, "That was your whole trouble . . ."<BR><BR> Lucy shouts, "You shouldn'ta hadn'ta oughtn'ta swang!!"<BR><BR>
It’s a line of a song, possibly a show tune?