I occasionally write Python scripts, but I always forget those very basic syntax. So I’m writing this cheat sheet in Python 3.
Iteration
Dictionary iteration for keys:
for key in d:
>>> for key in {1:2, 2:4}:
... print(key)
...
1
2
Dictionary iteration for values:
for v in d.values():
>>> for v in {1:2, 2:4}.values():
... print(v)
...
2
4
Dictionary iteration for items (key, value):
for key, value in d.items():
>>> for k, v in {1:2, 2:4}.items():
... print(k, v)
...
1 2
2 4
Insertion
Append an element into list:
list.append(e)
>>> l = [1, 2]
>>> l.append(3)
>>> l
[1, 2, 3]
Add an element into set:
s.add(e)
>>> s = {1, 2}
>>> s.add(3)
>>> s
{1, 2, 3}
If Statement
Ternary operator:
TrueExpression if Condition else FalseExpression
>>> l = []
>>> 'not empty' if l else 'empty'
'empty'