def fact(n):
	if n<= 1:
  		print(1) #if i use "return 1" here then no error but when i use here print(1) why the error occurred                                                                                 
	else:
		return n*fact(n-1)

f=fact(3)
print(f)

Error:
F:\Python Program>test.py
1
Traceback (most recent call last):
  File "F:\Python Program\test.py", line 7, in <module>
    f=fact(3)
  File "F:\Python Program\test.py", line 5, in fact
    return n*fact(n-1)
  File "F:\Python Program\test.py", line 5, in fact
    return n*fact(n-1)
TypeError: unsupported operand type(s) for *: 'int' and 'NoneType'