diff --git a/Project_Model/Libs/BPE/Utils/lag_checker_iterator.py b/Project_Model/Libs/BPE/Utils/lag_checker_iterator.py
new file mode 100644
index 0000000..28bbade
--- /dev/null
+++ b/Project_Model/Libs/BPE/Utils/lag_checker_iterator.py
@@ -0,0 +1,27 @@
+from collections import deque
+from typing import Generator, TypeVar
+
+T1 = TypeVar("T1")
+T2 = TypeVar("T2")
+T3 = TypeVar("T3")
+
+
+def iterator_with_checks(
+    generator: Generator[T1, T2, T3],
+) -> Generator[tuple[T1, bool], T2, T3]:
+
+    # Here we can ignore to catch stop iteration
+    #   we will propagate it
+    last_element = next(generator)
+
+    while True:
+
+        RETURN_ELEMENT = last_element
+        try:
+            element = next(generator)
+            last_element = element
+            yield (RETURN_ELEMENT, False)
+
+        except StopIteration:
+            yield (RETURN_ELEMENT, True)
+            break
diff --git a/Project_Model/Libs/BPE/Utils/special_regex_maker.py b/Project_Model/Libs/BPE/Utils/special_regex_maker.py
new file mode 100644
index 0000000..414eabf
--- /dev/null
+++ b/Project_Model/Libs/BPE/Utils/special_regex_maker.py
@@ -0,0 +1,9 @@
+import re
+
+
+def special_regex_maker(special_tokens: list[str]) -> re.Pattern:
+
+    REGEX_STR = "|".join(special_tokens)
+
+    return re.compile(REGEX_STR)
+