Usage of ^ in character class

Question

Why is it matching 1st one?
The characters are small letters and
r"[^A-Z]"--Does this search for only 1st pattern in the string or the whole string?
import re

pattern = r"[^A-Z]"

if re.search(pattern, "this is all quiet"):
print("Match 1")

if re.search(pattern, "AbCdEfG123"):
print("Match 2")

if re.search(pattern, "THISISALLSHOUTING"):
print("Match 3")

Answer 1

When ^ is used as the first character inside a regex class it means that you are looking for any character except those within the class. Your regex matches to any character that is not a capitol letter A-Z. This is why the last search is the only one that doesn't return true.

https://docs.python.org/3/howto/regex.html