Defer knitro import.

Author: eminyouskn

pyomo/contrib/solver/solvers/knitro/api.py

@@ -12,7 +12,7 @@
 
 from pyomo.common.dependencies import attempt_import
 
-import knitro
+# import knitro
 
-_, KNITRO_AVAILABLE = attempt_import("knitro")
+knitro, KNITRO_AVAILABLE = attempt_import("knitro")
 KNITRO_VERSION = knitro.__version__ if KNITRO_AVAILABLE else "0.0.0"