diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3354d4e1..129711b2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### Updated APIs
 ### Changed
 - Small refactor of AWS Signer classes for both sync and async clients ([866](https://github.com/opensearch-project/opensearch-py/pull/866))
+- Small refactor to fix overwriting the module files when generating apis ([874](https://github.com/opensearch-project/opensearch-py/pull/874))
 ### Deprecated
 ### Removed
 ### Fixed
diff --git a/test_opensearchpy/test_async/test_connection.py b/test_opensearchpy/test_async/test_connection.py
index c7d7b4a3..19c6222c 100644
--- a/test_opensearchpy/test_async/test_connection.py
+++ b/test_opensearchpy/test_async/test_connection.py
@@ -233,10 +233,8 @@ async def test_nowarn_when_test_uses_https_if_verify_certs_is_off(self) -> None:
                 assert w == []
             else:
                 assert len(w) == 1
-                assert (
-                    str(w[0].message) == "enable_cleanup_closed ignored because "
-                    "https://github.com/python/cpython/pull/118960 is fixed in "
-                    "Python version sys.version_info(major=3, minor=12, micro=7, releaselevel='final', serial=0)"
+                assert "https://github.com/python/cpython/pull/118960" in str(
+                    w[0].message
                 )
 
         assert isinstance(con.session, aiohttp.ClientSession)
diff --git a/utils/generate_api.py b/utils/generate_api.py
index 8b02e1be..06c63943 100644
--- a/utils/generate_api.py
+++ b/utils/generate_api.py
@@ -272,52 +272,52 @@ def dump(self) -> None:
             if "from " + utils + " import" not in line
         )
 
-        with open(self.filepath, "w", encoding="utf-8") as file:
-            if update_header is True:
-                file.write(
-                    self.header[:license_position]
-                    + "\n"
-                    + header_content
-                    + "\n\n"
-                    + "#replace_token#\n"
-                    + self.header[license_position:]
-                )
-            else:
-                file.write(
-                    self.header[:header_position]
-                    + "\n"
-                    + "#replace_token#\n"
-                    + self.header[header_position:]
-                )
-            for api in self._apis:
-                file.write(api.to_python())
+        module_content = ""
+        if update_header is True:
+            module_content += (
+                self.header[:license_position]
+                + "\n"
+                + header_content
+                + "\n\n"
+                + "#replace_token#\n"
+                + self.header[license_position:]
+            )
+        else:
+            module_content += (
+                self.header[:header_position]
+                + "\n"
+                + "#replace_token#\n"
+                + self.header[header_position:]
+            )
+        for api in self._apis:
+            module_content += api.to_python()
 
         # Generating imports for each module
         utils_imports = ""
-        file_content = ""
-        with open(self.filepath, encoding="utf-8") as file:
-            content = file.read()
-            keywords = [
-                "SKIP_IN_PATH",
-                "_normalize_hosts",
-                "_escape",
-                "_make_path",
-                "query_params",
-                "_bulk_body",
-                "_base64_auth_header",
-                "NamespacedClient",
-                "AddonClient",
-            ]
-            present_keywords = [keyword for keyword in keywords if keyword in content]
-
-            if present_keywords:
-                utils_imports = "from " + utils + " import"
-                result = f"{utils_imports} {', '.join(present_keywords)}"
-                utils_imports = result
-            file_content = content.replace("#replace_token#", utils_imports)
+
+        keywords = [
+            "SKIP_IN_PATH",
+            "_normalize_hosts",
+            "_escape",
+            "_make_path",
+            "query_params",
+            "_bulk_body",
+            "_base64_auth_header",
+            "NamespacedClient",
+            "AddonClient",
+        ]
+        present_keywords = [
+            keyword for keyword in keywords if keyword in module_content
+        ]
+
+        if present_keywords:
+            utils_imports = "from " + utils + " import"
+            result = f"{utils_imports} {', '.join(present_keywords)}"
+            utils_imports = result
+        module_content = module_content.replace("#replace_token#", utils_imports)
 
         with open(self.filepath, "w", encoding="utf-8") as file:
-            file.write(file_content)
+            file.write(module_content)
 
     @property
     def filepath(self) -> Any: