diff --git a/README.md b/README.md
index 548c6cc..dfb4e03 100644
--- a/README.md
+++ b/README.md
@@ -339,3 +339,7 @@ by Abolfazl (Abe) Arab ([@abearab](https://github.com/abearab)) as a Research As
 If you use ScreenPro2 in your research, please cite the following paper.
 
   Coming soon...
+
+## Development
+### Testing
+Tests can be easily run using the `pytest` framework.
diff --git a/environment.yml b/environment.yml
index dc52bce..dff04a3 100644
--- a/environment.yml
+++ b/environment.yml
@@ -29,3 +29,4 @@ dependencies:
       - simple_colors
       - adjustText
       - watermark
+      - pytest
diff --git a/screenpro/assays/__init__.py b/screenpro/assays/__init__.py
index 7e61487..dcc9988 100644
--- a/screenpro/assays/__init__.py
+++ b/screenpro/assays/__init__.py
@@ -262,7 +262,7 @@ def calculateDrugScreen(self, score_level: Literal["compare_reps", "compare_guid
                     n_reps=self.n_reps,
                     test=self.test, score_level=score_level,
                     count_filter_threshold=count_filter_threshold,
-                    count_filter_type=count_filter_type
+                    count_filter_type=count_filter_type,
                     **kwargs
                 )
                 self._add_phenotype_results(run_name, f'tau:{tau_name}', tau)