Python One‑Liner Tricks: Summation, List Deduplication, Comprehensions, Swapping, Sorting, Counting, Space Removal, Regex, Doubling, and Multiplication Table

Using a single line of code, you can sum integers from 1 to 100 with sum(range(1,101)) , remembering that range(1,101) excludes the upper bound.

To remove duplicates from a list, convert it to a set and back to a list in one line: list(set(my_list)) .

List comprehensions allow you to construct new lists succinctly, e.g., [expr for x in lst] or with a condition [expr for x in lst if cond] , enabling element transformation and filtering in a single expression.

Swap two values without a temporary variable using tuple unpacking: a, b = b, a .

Sort a list by the length of its string elements with my_list.sort(key=len) , which modifies the list in place.

Count occurrences of a specific character in a string using my_string.count('a') , which is case‑sensitive.

Remove spaces from a string either by my_string.replace(' ', '') or by splitting and joining: ''.join(my_string.split(' ')) .

Match Chinese characters using a regular expression pattern [\u4e00-\u9fa5]+ .

Double each element in a list with a one‑liner using list(map(lambda x: x*2, my_list)) .

Generate a formatted multiplication table in a single line: print('\n'.join(' '.join('%s*%s=%-2s'%(y,x,x*y) for y in range(1,x+1)) for x in range(1,10))) .