The re module provides regex. re.search() finds anywhere in a string, re.findall() gets all matches, and re.sub() replaces. Always use raw strings like r'\d+' for patterns to avoid escaping issues.
Regular Expressions (re module)
import re
text = "Call 555-1234 or 555-5678"
# Find all phone numbers
phones = re.findall(r"\d{3}-\d{4}", text)
print(phones) # ['555-1234', '555-5678']
# Match at start
if re.match(r"Call", text):
print("Starts with Call")
# Replace
cleaned = re.sub(r"\d{3}-\d{4}", "***", text)