Add print parameter to lark.tools.standalone.main

lark/tools/standalone.py

@@ -1,3 +1,5 @@
+from __future__ import print_function
+
 ###{standalone
 #
 #
@@ -117,7 +119,7 @@ def strip_docstrings(line_gen):
     return ''.join(res)
 
 
-def main(fobj, start):
+def main(fobj, start, print=print):
     lark_inst = Lark(fobj, parser="lalr", lexer="contextual", start=start)
 
     print('# The file was automatically generated by Lark v%s' % lark.__version__)