Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 26 2018, 23:26:24) 
[Clang 6.0 (clang-600.0.57)] on darwin
Type "copyright", "credits" or "license()" for more information.
>>> def test(x,y):
	print("s1")
	if x==0 and y==0:
		print("s2")
	elif x>0 and y>0:
		print("s3")
	elif x>0 or y>0:
		print("s4")
	else:
		print("s5")
	print("s6")
	return

>>> tes(0,0)
Traceback (most recent call last):
  File "<pyshell#13>", line 1, in <module>
    tes(0,0)
NameError: name 'tes' is not defined
>>> test(0,0)
s1
s2
s6
>>> test(0,1)
s1
s4
s6
>>> test(1,0)
s1
s4
s6
>>> test(1,1)
s1
s3
s6
>>> test(-1,-1)
s1
s5
s6
>>>