diff --git a/vllm/config.py b/vllm/config.py
index 0f315f21ec0c9..407c05924ec9a 100644
--- a/vllm/config.py
+++ b/vllm/config.py
@@ -257,7 +257,7 @@ def __init__(self,
                    f"'Please instead use `--hf-overrides '{hf_override!r}'`")
             warnings.warn(DeprecationWarning(msg), stacklevel=2)
 
-        self.pull_model_tokenizer_for_s3(model, tokenizer)
+        self.maybe_pull_model_tokenizer_for_s3(model, tokenizer)
 
         # The tokenizer version is consistent with the model version by default.
         if tokenizer_revision is None:
@@ -360,7 +360,9 @@ def __init__(self,
         self._verify_cuda_graph()
         self._verify_bnb_config()
 
-    def pull_model_tokenizer_for_s3(self, model: str, tokenizer: str) -> None:
+    def maybe_pull_model_tokenizer_for_s3(self, 
+                                          model: str,
+                                          tokenizer: str) -> None:
         if is_s3(model) or is_s3(tokenizer):
             try:
                 from vllm.transformers_utils.s3_utils import S3Model
diff --git a/vllm/model_executor/model_loader/loader.py b/vllm/model_executor/model_loader/loader.py
index 94e9e5c3d4f94..7c5ed9628930b 100644
--- a/vllm/model_executor/model_loader/loader.py
+++ b/vllm/model_executor/model_loader/loader.py
@@ -1301,7 +1301,7 @@ def _prepare_weights(self, model_name_or_path: str,
                 model_name_or_path, index_file, self.load_config.download_dir,
                 revision)
 
-        if len(hf_weights_files) == 0:
+        if not hf_weights_files:
             raise RuntimeError(
                 f"Cannot find any safetensors model weights with "
                 f"`{model_name_or_path}`")
diff --git a/vllm/transformers_utils/s3_utils.py b/vllm/transformers_utils/s3_utils.py
index 4474d3a914e15..66e4ec2c0e5a8 100644
--- a/vllm/transformers_utils/s3_utils.py
+++ b/vllm/transformers_utils/s3_utils.py
@@ -6,6 +6,7 @@
 import signal
 import tempfile
 from pathlib import Path
+from typing import Optional
 
 import boto3
 
@@ -26,7 +27,16 @@ def _filter_ignore(paths: list[str], patterns: list[str]) -> list[str]:
 
 def glob(s3=None,
          path: str = "",
-         allow_pattern: list[str] | None = None) -> list[str]:
+         allow_pattern: Optional[list[str]] = None) -> list[str]:
+    """
+    List full file names from S3 path and filter by allow pattern.
+
+    Args:
+        s3: S3 client to use.
+        path: The S3 path to list from.
+        allow_pattern: A list of patterns of which files to pull.
+
+    """
     if s3 is None:
         s3 = boto3.client("s3")
     bucket_name, _, paths = list_files(s3,
@@ -38,8 +48,19 @@ def glob(s3=None,
 def list_files(
         s3,
         path: str,
-        allow_pattern: list[str] | None = None,
-        ignore_pattern: list[str] | None = None) -> tuple[str, str, list[str]]:
+        allow_pattern: Optional[list[str]] = None,
+        ignore_pattern: Optional[list[str]] = None
+) -> tuple[str, str, list[str]]:
+    """
+    List files from S3 path and filter by pattern.
+
+    Args:
+        s3: S3 client to use.
+        path: The S3 path to list from.
+        allow_pattern: A list of patterns of which files to pull.
+        ignore_pattern: A list of patterns of which files not to pull.
+
+    """
     parts = path.removeprefix('s3://').split('/')
     prefix = '/'.join(parts[1:])
     bucket_name = parts[0]
@@ -58,6 +79,16 @@ def list_files(
 
 
 class S3Model:
+    """
+    A class representing a S3 model mirrored into a temporary directory.
+
+    Attributes:
+        s3: S3 client.
+        dir: The temporary created directory.
+
+    Methods:
+        pull_files(): Pull model from S3 to the temporary directory.
+    """
 
     def __init__(self) -> None:
         self.s3 = boto3.client('s3')
@@ -84,8 +115,17 @@ def new_handler(signum, frame):
 
     def pull_files(self,
                    s3_model_path: str = "",
-                   allow_pattern: list[str] | None = None,
-                   ignore_pattern: list[str] | None = None) -> None:
+                   allow_pattern: Optional[list[str]] = None,
+                   ignore_pattern: Optional[list[str]] = None) -> None:
+        """
+        Pull files from S3 storage into the temporary directory.
+
+        Args:
+            s3_model_path: The S3 path of the model.
+            allow_pattern: A list of patterns of which files to pull.
+            ignore_pattern: A list of patterns of which files not to pull.
+
+        """
         bucket_name, base_dir, files = list_files(self.s3, s3_model_path,
                                                   allow_pattern,
                                                   ignore_pattern)