diff --git a/.coveragerc.p2 b/.coveragerc.p2
new file mode 100644
index 0000000000000000000000000000000000000000..8acf35df89194c9c91a684741b7b8b45ce34b693
--- /dev/null
+++ b/.coveragerc.p2
@@ -0,0 +1,5 @@
+[report]
+exclude_lines =
+	pragma: no cover
+	raise NotImplementedError
+	def __download_file_p3
diff --git a/.coveragerc.p3 b/.coveragerc.p3
new file mode 100644
index 0000000000000000000000000000000000000000..2cf489e33518ff8c6bf3bc97ff9de4c2ce40776c
--- /dev/null
+++ b/.coveragerc.p3
@@ -0,0 +1,5 @@
+[report]
+exclude_lines =
+	pragma: no cover
+	raise NotImplementedError
+	def __download_file_p2
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 45a0dfbf5d45bf0f346cf4f9c1031ebfdc5c07d1..628552a6b5b8c8e24fffe4d70b06b1ceae37e635 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -38,14 +38,14 @@ tests:2.7:
     - pwd
   script:
     - python -V
-    - python -m pytest --pep8 --cov=allgo tests/
+    - python -m pytest --pep8 --cov=allgo  --cov-config=.coveragerc.p2 tests/
 
 # ----------------------------
 tests:3.7:
   stage: test
   script:
     - python -V
-    - python -m pytest --pep8 --cov=allgo tests/
+    - python -m pytest --pep8 --cov=allgo  --cov-config=.coveragerc.p3 tests/
 
 # ----------------------------
 sphinx:
diff --git a/allgo/__init__.py b/allgo/__init__.py
index 915ad5d6948c9f6ee59a1cf2f9cea390a6e1a0ab..984ebc1a27bc101e99dbf552b49990600c6f0afe 100644
--- a/allgo/__init__.py
+++ b/allgo/__init__.py
@@ -523,7 +523,7 @@ class Client:
                 return out_dict
 
         # should never goes here
-        return out_dict
+        return out_dict # pragma: no cover
 
     def get_log(self, job_id):
         """Generator of log file content.