Update primelib.py (#10209)

* Update primelib.py

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Tianyi Zheng <tianyizheng02@gmail.com>

Author: 3 people

maths/primelib.py

@@ -51,6 +51,10 @@ def is_prime(number: int) -> bool:
     True
     >>> is_prime(10)
     False
+    >>> is_prime(97)
+    True
+    >>> is_prime(9991)
+    False
     >>> is_prime(-1)
     Traceback (most recent call last):
         ...