import re
regex = re.compile(r"(\d{1,3})(\d{1,3})?(\d{1,4})?")
test_str = ("0\n"
"01\n"
"012\n"
"0123\n"
"01234\n"
"012345\n"
"0123456\n"
"01234567\n"
"012345678\n"
"0123456789")
matches = regex.finditer(test_str)
for match_num, match in enumerate(matches, start=1):
print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}")
for group_num, group in enumerate(match.groups(), start=1):
print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html