1. Swap Two Variables With One Line of Code
Can you think of a way to swap two variables without the help of a third temporary variable? Well, here it is:
a = 1
b = 2
a, b = b, a
2. Duplicate Strings Without Looping
name = "Banana"
print(name * 4)
Output:
BananaBananaBananaBanana
3. Reverse a String
sentence = "This is just a test"
reversed = sentence[::-1]print(reversed)
Output:
tset a tsuj si sihT
4. Squash a List of Strings Into One String
words = ["This", "is", "a", "Test"]
combined = " ".join(words)print(combined)
Output:
This is a Test
5. Comparison Chains
In Python, you can combine comparisons neatly together instead of splitting the statement into two or more parts. For example:
x = 100
res = 0 < x < 1000
print(res)
Output:
True
6. Find the Most Frequent Element in a List
test = [6, 2, 2, 3, 4, 2, 2, 90, 2, 41]
most_frequent = max(set(test), key = test.count)
print(most_frequent)
Output:
2
7. Unpack List to Separate Variables
You can neatly unpack a list of elements to separate variables as long as the number of variables remains the same as the number of elements in the list.
For example:
arr = [1, 2, 3]
a,b,c = arrprint(a, b, c)
Output:
1 2 3
8. One-Liner If-Else Statements
In Python, one-liner if-else statements are known as ternary operators or conditional operators. For example:
age = 30
age_group = "Adult"
if age > 18
else "Child"print(age_group)
Output:
Adult
Generally, a conditional operator follows this pattern for your convenience:
true_expression if condition else false_expression
9. Loop Through a List With One Line of Code
You can use comprehensions to loop through a list with one line of code. For example, let’s raise each number in a list to the second power:
numbers = [1, 2, 3, 4, 5]
squared_numbers = [num * num for num in numbers]
print(squared_numbers)
Output:
[1, 4, 9, 16, 25]
Note: Comprehensions are not just limited to working with lists. You can use comprehensions in a similar one-liner fashion with dictionaries, sets, and generators as well.
Let’s see another example by using dictionary comprehension to raise the values of a dictionary to the second power:
dict1 = {'a': 1, 'b': 2, 'c': 3, 'd': 4}squared_dict = {key: num * num for (key, num) in dict1.items()}
print(squared_dict)Output:
{'a': 1, 'b': 4, 'c': 9, 'd': 16}10. Simplify If Statements
Instead of this horrible mess:
if n == 0 or n == 1 or n == 2 or n == 3 or n == 4 or n == 5:
You can simply do this:
if n in [0, 1, 2, 3, 4, 5]
