-    if re.match(r'.*\.7z', input_filename):
-        cmd = ["7za", "x", "-so", input_filename, '*.xml'] 
-    elif re.match(r'.*\.gz', input_filename):
-        cmd = ["zcat", input_filename] 
-    elif re.match(r'.*\.bz2', input_filename):
+    if re.match(r'.*\.7z$', input_filename):
+        cmd = ["7za", "x", "-so", input_filename, '*'] 
+    elif re.match(r'.*\.gz$', input_filename):