SW-516: added input parameter

LCS/PyCommon/subprocess_utils.py

@@ -34,10 +34,10 @@ def _convert_bytes_tuple_to_strings(bytes_tuple):
                  else x
                  for x in bytes_tuple)
 
-def communicate_returning_strings(proc):
+def communicate_returning_strings(proc, input=None):
     """Helper function for subprocess.communicate() which changed from python2 to python3.
     This function waits for the subprocess to finish and returns the stdout and stderr as utf-8 strings, just like python2 did."""
-    return _convert_bytes_tuple_to_strings(proc.communicate())
+    return _convert_bytes_tuple_to_strings(proc.communicate(input=input))
 
 def check_output_returning_strings(*popenargs, timeout=None, **kwargs):
     """Helper function for subprocess.check_output(...) which changed from python2 to python3.