This Python RegEx lesson is for a beginner. Read the short notes, run each example, then change one name or number and run it again.
The re module searches text by pattern. \d means a digit. + means one or more. Raw strings, written with an r before the quote, keep backslashes literal.
search returns a match object or None. group() is the text that matched.
Example 1: Start here
Test a pattern on a short sample before you trust it on a full file.
import re # load a tool that comes with Python
phone = "Call 8190098289 today" # text
found = re.search(r"\d+", phone) # a match, or None when nothing fits
print(found.group())
Example 2: Search
\d+ means one or more digits. group returns the matched text.
import re # load a tool that comes with Python
print(re.search(r"\d+", "Batch 12").group())
Example 3: Find all
findall returns every match as a list.
import re # load a tool that comes with Python
print(re.findall(r"\d+", "Room 3 and room 12"))
Example 4: Replace
sub replaces each match with the new text.
import re # load a tool that comes with Python
print(re.sub(r"\d+", "#", "Batch 12"))
Test a pattern on a short sample before you trust it on a full file.
