Pynumero spawns multiple instances of script file from which it's called

[dallan-keylogic]

Want to leave a record of this Pyomo issue in the IDAES repo, in case any IDAES user encounters it.

[lbianchi-lbl]

For cross-project reference, this is related to watertap-org/watertap#387, with a simple workaround described here.

[ksbeattie]

While someone might be interested in finding out what/where/why this script is getting imported (and run without the __main__ check), that's beyond our scope right now.