wish help you to fix your issue After reading delnan's comment, I realized that pypy could not find pulp because it did not know where to look for it. It was complaining: from pulp import *
PuLP producing LP files that are solvable by command line CBC, but PuLP reports a undefined solution
By : YordanoMP
Date : March 29 2020, 07:55 AM
will help you This seems to be caused by an error with the older version of cbc shipped with pulp 1.5.6 I will repackage a newer version of cbc with pulp 1.5.7 ASAP. Also you can use your other version of CBC (if it is on the path) by using the COIN_CMD solver.