added aserts for file existence checking

app.py

@@ -66,15 +66,20 @@ def main_func(input_file_list):
 
         work_dir = os.path.join(tempdir,f"work_dir")
         compute_lungqia_wrapper(seri_file,tempdir,lungseg_enable=True,work_dir=work_dir)
-        assert(os.path.exists(lungqia_csv))
         novsl_nifti_file = os.path.join(work_dir,"novsl.nii.gz")
         wlung_nifti_file = os.path.join(work_dir,"wlung.nii.gz")
         lungqia_csv = os.path.join(tempdir,"lungqia_results.csv")
 
+        assert(os.path.exists(novsl_nifti_file))
+        assert(os.path.exists(wlung_nifti_file))
+        assert(os.path.exists(lungqia_csv))
+
         transform_lungqia_to_mlqlf(lungqia_csv,novsl_nifti_file,wlung_nifti_file,tempdir)
         mlqlf_csv_file = os.path.join(tempdir,"mlqlf.csv")
         mlqlf_nifti_file = os.path.join(tempdir,"mlqlf.nii.gz")
+
         assert(os.path.exists(mlqlf_csv_file))
+        assert(os.path.exists(mlqlf_nifti_file))
 
         my_uid = uuid.uuid4().hex
         output_pdf_file = os.path.join('/tmp',f'{my_uid}.pdf')