diff --git a/DPF/dataset_reader.py b/DPF/dataset_reader.py
index 04b277e..848b327 100644
--- a/DPF/dataset_reader.py
+++ b/DPF/dataset_reader.py
@@ -13,7 +13,7 @@
 )
 
 
-def help_reader(filesystem: FileSystem, required_columns: Optional[list[str]], path: str):
+def help_reader(filesystem: FileSystem, required_columns: Optional[List[str]], path: str):
     df = filesystem.read_dataframe(path)
 
     if required_columns:
diff --git a/DPF/processors/processor.py b/DPF/processors/processor.py
index 435b6d6..8a2b3fc 100644
--- a/DPF/processors/processor.py
+++ b/DPF/processors/processor.py
@@ -170,7 +170,7 @@ def to_sharded_files(
         max_files_in_shard: int = 1000,
         datafiles_ext: str = "csv",
         meta_columns: Optional[List[str]] = None,
-        keys_mapping: Optional[dict[str, str]] = None,
+        keys_mapping: Optional[Dict[str, str]] = None,
         workers: int = 8,
         pbar: bool = True
     ):
@@ -196,7 +196,7 @@ def to_shards(
         datafiles_ext: str = "csv",
         archives_ext: Optional[str] = "tar",
         meta_columns: Optional[List[str]] = None,
-        keys_mapping: Optional[dict[str, str]] = None,
+        keys_mapping: Optional[Dict[str, str]] = None,
         workers: int = 8,
         pbar: bool = True
     ):
diff --git a/DPF/processors/writers/sharded_files_writer.py b/DPF/processors/writers/sharded_files_writer.py
index d62f820..036bc9d 100644
--- a/DPF/processors/writers/sharded_files_writer.py
+++ b/DPF/processors/writers/sharded_files_writer.py
@@ -18,7 +18,7 @@ def __init__(
         self,
         filesystem: FileSystem,
         destination_dir: str,
-        keys_mapping: Optional[dict[str, str]] = None,
+        keys_mapping: Optional[Dict[str, str]] = None,
         max_files_in_shard: int = 1000,
         datafiles_ext: str = "csv",
     ) -> None:
diff --git a/DPF/processors/writers/shards_writer.py b/DPF/processors/writers/shards_writer.py
index 0a11f88..30c167b 100644
--- a/DPF/processors/writers/shards_writer.py
+++ b/DPF/processors/writers/shards_writer.py
@@ -20,7 +20,7 @@ def __init__(
         self,
         filesystem: FileSystem,
         destination_dir: str,
-        keys_mapping: Optional[dict[str, str]] = None,
+        keys_mapping: Optional[Dict[str, str]] = None,
         max_files_in_shard: Optional[int] = 1000,
         datafiles_ext: Optional[str] = "csv",
         archives_ext: Optional[str] = "tar",