Comprehensions & generators
List/dict/set comprehensions, generator expressions, and lazy iteration.
How to Sort Data with Comprehensions and Generators in Python
Sort a list of tuples by a key, then use a list comprehension to extract names and a generator to square high ranks.
data = [("Anna", 3), ("Ben", 1), ("Clara", 2), ("Dan", 5), ("Eve", 4)]
# Comprehension: list of tuples (name, rank) sorted ascending by rank
sorted_by_rank = sorted(data, key=lambda x: x[1])
# Comprehension: extract just the names in rank order
names_in_rank_order = [name for name, rank in sorted_by_rank]
# Generat…Merge Sorted Iterators with a Heap Generator in Python
Merge multiple sorted iterators into a single sorted stream using a heap and generator, yielding values lazily in order.
import heapq
def merge_sorted_iterators(*iterators):
heap = []
for idx, iterator in enumerate(iterators):
try:
value = next(iterator)
heapq.heappush(heap, (value, idx, iterator))
except StopIteration:
continue
while heap:
value, idx, iterator = …Set Comprehension for Unique Word Lengths in Python
Use a set comprehension to extract unique word lengths from a string, then sort and print the result.
text = "hello world hello python programming"
word_lengths = {len(word) for word in text.split()}
print("Unique word lengths:", word_lengths)
print("Sorted:", sorted(word_lengths))Browse by section
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Comprehensions & generators — Python code examples
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This page collects comprehensions & generators snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.
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