create left son of root
def set_left ( key , parent ) : NEW_LINE INDENT if tree [ parent ] == None : NEW_LINE INDENT print ( " Can ' t ▁ set ▁ child ▁ at " , ( parent * 2 ) + 1 , " , ▁ no ▁ parent ▁ found " ) NEW_LINE DEDENT else : NEW_LINE INDENT tree [ ( parent * 2 ) + 1 ] = key NEW_LINE DEDENT DEDENT