fix syntax

app.py

@@ -53,7 +53,7 @@ chart_data = pd.DataFrame({
     "run_accession_meta": estimated_expression_meta["run_accession"],
     "study_accession": estimated_expression_meta["study_accession"]}) 
 
-print(f"run_ids are equal: {sum(chart_data["run_accession"] == chart_data["run_accession_meta"])}")
+print(f"run_ids are equal: {sum(chart_data['run_accession'] == chart_data['run_accession_meta'])}")
 
 chart = (
    alt.Chart(chart_data)