How to Process Text with Lists and Loops in Python

Iterate over a list of text lines to count words, show uppercase versions, and report character counts per line.

Easy Python 3.6+ Aug 9, 2026 Lists & loops 17 views 0 copies

lists loops enumerate text-processing beginner

Python code

19 lines

Python 3.6+

# text_processor.py

def process_text(lines):
    """Count words, show uppercase, and count characters per line."""
    total_words = 0
    print("Line-by-line analysis:")
    for i, line in enumerate(lines, start=1):
        words = line.split()
        total_words += len(words)
        print(f"  Line {i}: {len(words)} words, {len(line)} chars, UPPER: {line.upper()}")
    print(f"Total words: {total_words}")

if __name__ == "__main__":
    sample_lines = [
        "hello world",
        "pythonskillset is fun",
        "learn lists and loops"
    ]
    process_text(sample_lines)

Output

stdout

Line-by-line analysis:
  Line 1: 2 words, 11 chars, UPPER: HELLO WORLD
  Line 2: 3 words, 20 chars, UPPER: PYTHONSKILLSET IS FUN
  Line 3: 4 words, 22 chars, UPPER: LEARN LISTS AND LOOPS
Total words: 9

How it works

The enumerate function pairs each line with its index starting at 1, giving you both the line number and the text. line.split() splits on whitespace, so it counts words regardless of extra spacing. len(line) returns the raw character count including spaces. The f-string formatting embeds variables directly for readable output. Calling process_text inside the if __name__ == "__main__" guard lets the script run standalone without executing when imported.

Common mistakes

Using `range(len(lines))` instead of `enumerate`, which forces manual index tracking
Counting characters with `len(line.split())` instead of `len(line)` for total characters
Forgetting the `start=1` argument, so line numbers start at 0 instead of 1

Variations

Use a list comprehension to collect results and print them later
Read lines from a file with `open()` instead of a hardcoded list

Real-world use cases

Analyzing log files to summarize word counts per line for debugging.
Generating formatted reports from customer feedback lines in a support tool.
Preprocessing free-text input fields before saving them to a database.

How to Process Text with Lists and Loops in Python

Python code

Output

How it works

Common mistakes

Variations

Real-world use cases

More from Lists & loops

Tutorials

Quizzes

Python code

Output

How it works

Common mistakes

Variations

Real-world use cases

More from Lists & loops

Keep learning

Tutorials

Quizzes