bugfix: Add empty list detection for find_max/min (#4881)

* bugfix: Add empty list detection for find_max/min

* fix shebangs check

maths/find_min.py

@@ -1,4 +1,7 @@
-def find_min(nums):
+from __future__ import annotations
+
+
+def find_min(nums: list[int | float]) -> int | float:
     """
     Find Minimum Number in a List
     :param nums: contains elements
@@ -10,7 +13,15 @@ def find_min(nums):
     True
     True
     True
+    >>> find_min([0, 1, 2, 3, 4, 5, -3, 24, -56])
+    -56
+    >>> find_min([])
+    Traceback (most recent call last):
+        ...
+    ValueError: find_min() arg is an empty sequence
     """
+    if len(nums) == 0:
+        raise ValueError("find_min() arg is an empty sequence")
     min_num = nums[0]
     for num in nums:
         if min_num > num:
@@ -18,9 +29,7 @@ def find_min(nums):
     return min_num
 
 
-def main():
-    assert find_min([0, 1, 2, 3, 4, 5, -3, 24, -56]) == -56
-
-
 if __name__ == "__main__":
-    main()
+    import doctest
+
+    doctest.testmod(verbose=True)