Python Tips and Tricks: Variable Swapping, Comprehensions, Counter, JSON Pretty‑Print, FizzBuzz, and More

Python’s concise syntax enables many powerful tricks that simplify everyday programming tasks. The article begins by showing how to swap two variables without a temporary placeholder using the one‑liner a, b = b, a , followed by a quick demonstration of printing the swapped values.

It then introduces list, set, and dictionary comprehensions, illustrating how to generate a new list with another_list = [x + 1 for x in some_list] , create a set of even numbers with even_set = {x for x in some_list if x % 2 == 0} , and build a boolean mapping dictionary with d = {x: x % 2 == 0 for x in range(1, 11)} . The same syntax can also produce a literal set directly: my_set = {1, 2, 3, 4} .

The collections.Counter class is highlighted for counting occurrences in a string: c = Counter('hello world') and retrieving the most common items with c.most_common(2) . The article also covers pretty‑printing JSON using the built‑in json module, showing both compact and indented output via json.dumps(data, indent=2) .

Inline conditional expressions are demonstrated with print('Hello' if True else 'World') . List concatenation and string formatting examples combine two football‑team lists, and the + operator is used to join strings and numbers.

Numeric comparisons can be chained in Python, as shown by if 3 > x > 1: print(x) . Iterating over two lists simultaneously is achieved with for a, b in zip(nfc, afc): print(a + ' vs. ' + b) , while enumerate provides index‑value pairs for a list.

Classic list comprehension for filtering even numbers is transformed into a more compact form: even = [n for n in numbers if n % 2 == 0] . A dictionary comprehension that swaps keys and values from an enumerated list is shown as {key: value for value, key in enumerate(teams)} .

Other useful snippets include initializing a list with repeated values ( items = [0] * 3 ), converting a list to a comma‑separated string ( ', '.join(teams) ), safely retrieving dictionary values with data.get('admin', False) , and various list‑slicing techniques ( x[:3] , x[1:5] , x[::2] , etc.).

Additional examples cover the itertools.combinations function for generating pairwise combinations of a list, and a playful demonstration that reassigns False = True and uses an if statement to print "Hello".