diff --git a/ocr_pyflow b/ocr_pyflow
index 974cea6..00e8a6e 100755
--- a/ocr_pyflow
+++ b/ocr_pyflow
@@ -115,7 +115,7 @@ class OCRWorkflow(WorkflowRunner):
                 os.path.join(job["output_dir"], "tmp", "ocropus-nlbin"),
                 os.path.join(job["output_dir"], "tmp", "tesseract"),
                 os.path.join(job["output_dir"], "tmp", "tiff_files"))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             mkdir_jobs.append(self.addTask(label="mkdir_job_-_%i" % (mkdir_job_number), command=cmd))
 
 
@@ -140,14 +140,14 @@ class OCRWorkflow(WorkflowRunner):
                 os.path.join(job["output_dir"], "tmp", "tiff_files", os.path.basename(job["path"]).rsplit(".", 1)[0] + ".pdf"),
                 os.path.join(job["output_dir"], "tmp", "tiff_files", os.path.basename(job["path"]).rsplit(".", 1)[0]),
                 os.path.join(job["output_dir"], "tmp", "tiff_files", os.path.basename(job["path"]).rsplit(".", 1)[0] + ".pdf"))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             split_jobs.append(self.addTask(label="split_job_-_%i" % (split_job_number), command=cmd, dependencies=mkdir_jobs))
         for job in self.jobs["pdf"]:
             split_job_number += 1
             cmd = "pdftoppm %s %s -tiff -r 300 -tiffcompression lzw -cropbox" % (
                 job["path"],
                 os.path.join(job["output_dir"], "tmp", "tiff_files", os.path.basename(job["path"]).rsplit(".", 1)[0]))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             split_jobs.append(self.addTask(label="split_job_-_%i" % (split_job_number), command=cmd, dependencies=mkdir_jobs))
 
 
@@ -162,7 +162,7 @@ class OCRWorkflow(WorkflowRunner):
             cmd = "ocropus-nlbin -o %s %s" % (
                 os.path.join(job["output_dir"], "tmp", "ocropus-nlbin"),
                 os.path.join(job["output_dir"], "tmp", "tiff_files", os.path.basename(job["path"]).rsplit(".", 1)[0] + "-*.tif"))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             ocropusnlbin_jobs.append(self.addTask(label="ocropusnlbin_job_-_%i" % (ocropusnlbin_job_number), command=cmd, dependencies=split_jobs))
 
 
@@ -182,7 +182,7 @@ class OCRWorkflow(WorkflowRunner):
                     os.path.join(job["output_dir"], "tmp", "tesseract", file.rsplit(".", 2)[0]),
                     self.lang,
                     "pdf" if self.pdf else "")
-                cmd = shlex.escape(cmd);
+                cmd = shlex().escape(cmd);
                 tesseract_jobs.append(self.addTask(label="tesseract_job_-_%i" % (tesseract_job_number), command=cmd, dependencies=ocropusnlbin_jobs, nCores=min(4, self.nCores)))
 
 
@@ -198,7 +198,7 @@ class OCRWorkflow(WorkflowRunner):
                 cmd = "pdftk %s cat output %s" % (
                     os.path.join(job["output_dir"], "tmp", "tesseract", "*.pdf"),
                     os.path.join(job["output_dir"], os.path.basename(job["path"].rsplit(".", 1)[0] + ".pdf")))
-                cmd = shlex.escape(cmd);
+                cmd = shlex().escape(cmd);
                 pdf_merge_jobs.append(self.addTask(label="pdf_merge_job_-_%i" % (pdf_merge_job_number), command=cmd, dependencies=tesseract_jobs))
 
 
@@ -213,7 +213,7 @@ class OCRWorkflow(WorkflowRunner):
                 pdf_to_txt_job_number += 1
                 cmd = "pdftotext -raw %s" % (
                     os.path.join(job["output_dir"], os.path.basename(job["path"].rsplit(".", 1)[0] + ".pdf")))
-                cmd = shlex.escape(cmd);
+                cmd = shlex().escape(cmd);
                 pdf_merge_jobs.append(self.addTask(label="pdf_to_txt_job_-_%i" % (pdf_to_txt_job_number), command=cmd, dependencies=pdf_merge_jobs))
 
 
@@ -228,7 +228,7 @@ class OCRWorkflow(WorkflowRunner):
             cmd = "mv %s %s" % (
                 os.path.join(job["output_dir"], "tmp", "tesseract", "*.hocr"),
                 os.path.join(job["output_dir"], "hocr_files"))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             move_hocr_jobs.append(self.addTask(label="move_hocr_job_-_%i" % (move_hocr_job_number), command=cmd, dependencies=tesseract_jobs))
 
 
@@ -243,7 +243,7 @@ class OCRWorkflow(WorkflowRunner):
             cmd = "parse_hocr %s %s" % (
                 os.path.join(job["output_dir"], "hocr_files"),
                 os.path.join(os.path.join(job["output_dir"], os.path.basename(job["path"]).rsplit(".", 1)[0] + ".xml")))
-            cmd = shlex.escape(cmd);
+            cmd = shlex().escape(cmd);
             hocr_to_teip5_jobs.append(self.addTask(label="hocr_to_teip5_job_-_%i" % (hocr_to_teip5_job_number), command=cmd, dependencies=move_hocr_jobs))
 
 
@@ -258,7 +258,7 @@ class OCRWorkflow(WorkflowRunner):
             for job in self.jobs["images"] + self.jobs["pdf"]:
                 cleanup_job_counter += 1
                 cmd = "rm -r %s" % (os.path.join(job["output_dir"], "tmp"))
-                cmd = shlex.escape(cmd);
+                cmd = shlex().escape(cmd);
                 cleanup_jobs.append(self.addTask(label="cleanup_job_-_%i" % (cleanup_job_counter), command=cmd))