Merge pull request #4700 from minrk/ifmain

use if main block in entry points

setupbase.py

@@ -334,8 +334,9 b' def find_entry_points():'
 
 script_src = """#!{executable}
 # This script was automatically generated by setup.py
-from {mod} import {func}
-{func}()
+if __name__ == '__main__':
+    from {mod} import {func}
+    {func}()
 """
 
 class build_scripts_entrypt(build_scripts):