Answers for "return code error python"

return code error python

from turtle import*
from random import randrange
from freegames import square, vector

food = vector(0,0)
snake = [vector(10,0)]
aim = vector(0,-10)
def change(x,y):
  aim.x=x
  aim.y=y

def inside(head):
    return -200<head.x<190 and -200 <head.y <190
def move():
        head=snake[-1].copy()
        head.move(aim)

        if not inside(head) or head in snake:
            square(head.x,head.y,9,'red')
update()

a
return

snake.append()
print('snake',len(snake))
if head==food: food.x = randrange(-15,15)*10
food.y = randrange(-15,15)*10

else
snake.pop(0)

clear()

for body in snake:
    square(body.x,body.y,9,'green')

    square(food.x,food.y,9,'red')
    update()
    ontime(move, 100)

hideturtle()
tracer(False)
listen()
onkey(lambda:changes(10,0),'right')
onkey(lambda:changes(-10,0),'left')
onkey(lambda:changes(0,10),'up')
onkey(lambda:changes(0,-10),'down')

move()
done()

return code error python

File "c:\Users\deoll\Desktop\java\python test\pythontest.py", line 30
    else
    ^
SyntaxError: invalid syntax
PS C:\Users\deoll\Desktop\java>