Fix mypy error

python/sdk/merlin/requirements.py

@@ -2,7 +2,7 @@
 from collections import namedtuple
 from itertools import filterfalse
 from pathlib import Path
-from typing import Dict, List, Optional
+from typing import Any, Dict, List, Optional, Union
 
 import yaml
 from packaging.requirements import Requirement
@@ -18,8 +18,8 @@ def get_default_merlin_requirements():
 
 
 def process_conda_env(
-    conda_env: Dict = None,
-    python_version: str = "3.10.*",
+    conda_env: Any,
+    python_version: Optional[str] = "3.10.*",
     additional_merlin_reqs: Optional[List[str]] = None,
 ):
     """
@@ -54,17 +54,18 @@ def process_conda_env(
     pip_reqs = _get_pip_deps(conda_env)
     pip_reqs, constraints = _parse_pip_requirements(pip_reqs)
 
-    for additional_merlin_req in additional_merlin_reqs:
-        exist = False
-        for pip_req in pip_reqs:
-            pip_req_obj = Requirement(pip_req)
-            additional_merlin_req_obj = Requirement(additional_merlin_req)
-            if pip_req_obj.name.lower() == additional_merlin_req_obj.name.lower():
-                exist = True
-                break
-
-        if not exist:
-            pip_reqs.insert(0, additional_merlin_req)
+    if additional_merlin_reqs:
+        for additional_merlin_req in additional_merlin_reqs:
+            exist = False
+            for pip_req in pip_reqs:
+                pip_req_obj = Requirement(pip_req)
+                additional_merlin_req_obj = Requirement(additional_merlin_req)
+                if pip_req_obj.name.lower() == additional_merlin_req_obj.name.lower():
+                    exist = True
+                    break
+
+            if not exist:
+                pip_reqs.insert(0, additional_merlin_req)
 
     if constraints:
         pip_reqs.append(f"-c {_CONSTRAINTS_FILE_NAME}")