Added different queries & unittests

src/cpl_query/_query/first_query.py

@@ -0,0 +1,17 @@
+from typing import Optional
+
+from cpl_query.extension.iterable_abc import IterableABC
+
+
+def first_query(_list: IterableABC) -> any:
+    if len(_list) == 0:
+        raise Exception('Index out of range')
+
+    return _list[0]
+
+
+def first_or_default_query(_list: IterableABC) -> Optional[any]:
+    if len(_list) == 0:
+        return None
+
+    return _list[0]