Indentation Errors

The spacing should be even and uniform throughout. Improper indentation can cause an IndentationError or cause the program to do something unexpected. The following example raises an IndentationError:

a = 7
if a > 5:
  print "foo"
else:
  print "bar"
 print "done"

Or if the line following a colon is not indented, an IndentationError will also be raised:

if True:
print "true"

If you add indentation where it doesn’t belong, an IndentationError will be raised:

if  True:
    a = 6
        b = 5

If you forget to un-indent functionality could be lost. In this example None is returned instead of the expected False:

def isEven(a):
    if a%2 ==0:
        return True
        #this next line should be even with the if
        return False
print isEven(7)