diff --git a/stack.sh b/stack.sh
index 0f9d57b..7119e5f 100755
--- a/stack.sh
+++ b/stack.sh
@@ -415,11 +415,8 @@
 
 # Ensure python is installed
 # --------------------------
-install_python3
+install_python
 
-if ! python3_enabled; then
-    is_package_installed python || install_package python
-fi
 
 # Configure Logging
 # -----------------
@@ -497,14 +494,14 @@
             _of_args="$_of_args --no-timestamp"
         fi
         # Set fd 1 and 2 to write the log file
-        exec 1> >( $TOP_DIR/tools/outfilter.py $_of_args -o "${LOGFILE}" ) 2>&1
+        exec 1> >( $PYTHON $TOP_DIR/tools/outfilter.py $_of_args -o "${LOGFILE}" ) 2>&1
         # Set fd 6 to summary log file
-        exec 6> >( $TOP_DIR/tools/outfilter.py -o "${SUMFILE}" )
+        exec 6> >( $PYTHON $TOP_DIR/tools/outfilter.py -o "${SUMFILE}" )
     else
         # Set fd 1 and 2 to primary logfile
-        exec 1> >( $TOP_DIR/tools/outfilter.py -o "${LOGFILE}" ) 2>&1
+        exec 1> >( $PYTHON $TOP_DIR/tools/outfilter.py -o "${LOGFILE}" ) 2>&1
         # Set fd 6 to summary logfile and stdout
-        exec 6> >( $TOP_DIR/tools/outfilter.py -v -o "${SUMFILE}" >&3 )
+        exec 6> >( $PYTHON $TOP_DIR/tools/outfilter.py -v -o "${SUMFILE}" >&3 )
     fi
 
     echo_summary "stack.sh log $LOGFILE"
@@ -521,7 +518,7 @@
         exec 1>/dev/null 2>&1
     fi
     # Always send summary fd to original stdout
-    exec 6> >( $TOP_DIR/tools/outfilter.py -v >&3 )
+    exec 6> >( $PYTHON $TOP_DIR/tools/outfilter.py -v >&3 )
 fi
 
 # Basic test for ``$DEST`` path permissions (fatal on error unless skipped)
@@ -557,9 +554,9 @@
             generate-subunit $DEVSTACK_START_TIME $SECONDS 'fail' >> ${SUBUNIT_OUTPUT}
         fi
         if [[ -z $LOGDIR ]]; then
-            $TOP_DIR/tools/worlddump.py
+            ${PYTHON} $TOP_DIR/tools/worlddump.py
         else
-            $TOP_DIR/tools/worlddump.py -d $LOGDIR
+            ${PYTHON} $TOP_DIR/tools/worlddump.py -d $LOGDIR
         fi
     else
         # If we error before we've installed os-testr, this will fail.