build: move meta-shebang back to configure

PR-URL: #22450
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

configure

@@ -0,0 +1,28 @@
+#!/bin/sh
+
+# Locate python2 interpreter and re-execute the script.  Note that the
+# mix of single and double quotes is intentional, as is the fact that
+# the ] goes on a new line.
+_=[ 'exec' '/bin/sh' '-c' '''
+which python2.7 >/dev/null && exec python2.7 "$0" "$@"
+which python2 >/dev/null && exec python2 "$0" "$@"
+exec python "$0" "$@"
+''' "$0" "$@"
+]
+del _
+
+import sys
+from distutils.spawn import find_executable as which
+if sys.version_info[0] != 2 or sys.version_info[1] not in (6, 7):
+  sys.stderr.write('Please use either Python 2.6 or 2.7')
+
+  python2 = which('python2') or which('python2.6') or which('python2.7')
+
+  if python2:
+    sys.stderr.write(':\n\n')
+    sys.stderr.write('  ' + python2 + ' ' + ' '.join(sys.argv))
+
+  sys.stderr.write('\n')
+  sys.exit(1)
+
+import configure

configure.py

@@ -1,30 +1,4 @@
-#!/bin/sh
-
-# Locate python2 interpreter and re-execute the script.  Note that the
-# mix of single and double quotes is intentional, as is the fact that
-# the ] goes on a new line.
-_=[ 'exec' '/bin/sh' '-c' '''
-which python2.7 >/dev/null && exec python2.7 "$0" "$@"
-which python2 >/dev/null && exec python2 "$0" "$@"
-exec python "$0" "$@"
-''' "$0" "$@"
-]
-del _
-
 import sys
-from distutils.spawn import find_executable as which
-if sys.version_info[0] != 2 or sys.version_info[1] not in (6, 7):
-  sys.stderr.write('Please use either Python 2.6 or 2.7')
-
-  python2 = which('python2') or which('python2.6') or which('python2.7')
-
-  if python2:
-    sys.stderr.write(':\n\n')
-    sys.stderr.write('  ' + python2 + ' ' + ' '.join(sys.argv))
-
-  sys.stderr.write('\n')
-  sys.exit(1)
-
 import errno
 import optparse
 import os
@@ -35,6 +9,7 @@
 import subprocess
 import shutil
 import string
+from distutils.spawn import find_executable as which
 
 # If not run from node/, cd to node/.
 os.chdir(os.path.dirname(__file__) or '.')