- Immediately inside parentheses, brackets or braces.
Yes: spam(ham[1], {eggs: 2})
No: spam( ham[ 1 ], { eggs: 2 } )
- Immediately before a comma, semicolon, or colon:
Yes: if x == 4: print x, y; x, y = y, x
No: if x == 4 : print x , y ; x , y = y , x
- Immediately before the open parenthesis that starts the argument
list of a function call:
Yes: spam(1)
No: spam (1)
- Immediately before the open parenthesis that starts an indexing or
slicing:
Yes: dict['key'] = list[index]
No: dict ['key'] = list [index]
- More than one space around an assignment (or other) operator to
align it with another.
Yes:
x = 1
y = 2
long_variable = 3
No:
x = 1
y = 2
long_variable = 3
Other Recommendations
- Always surround these binary operators with a single space on
either side: assignment (=), augmented assignment (+=, -= etc.),
comparisons (==, <, >, !=, <>, <=, >=, in, not in, is, is not),
Booleans (and, or, not).
- Use spaces around arithmetic operators:
Yes:
i = i + 1
submitted += 1
x = x * 2 - 1
hypot2 = x * x + y * y
c = (a + b) * (a - b)
No:
i=i+1
submitted +=1
x = x*2 - 1
hypot2 = x*x + y*y
c = (a+b) * (a-b)
- Don't use spaces around the '=' sign when used to indicate a
keyword argument or a default parameter value.
Yes:
def complex(real, imag=0.0):
return magic(r=real, i=imag)
No:
def complex(real, imag = 0.0):
Style Guide For Python Code
Start from the beginning
