fix path for gurobi on windows

Former-commit-id: 223e75e [formerly 97b9de6]
Former-commit-id: 22588a0

Author: h-g-s

mip/callbacks.py

@@ -15,7 +15,7 @@ class CutsGenerator:
     """abstract class for implementing cut generators"""
 
     def __init__(self):
-        pass
+        self.lazyConstraints = False
 
     def generate_cuts(self, model: Model):
         """Method called by the solver engine to generate cuts

mip/constants.py

@@ -2,7 +2,7 @@
 
 from enum import Enum
 
-VERSION = '1.3.9'
+VERSION = '1.3.10'
 
 # epsilon number (practical zero)
 EPS = 10e-6

mip/gurobi.py

@@ -5,6 +5,7 @@
 import os.path
 from glob import glob
 from os import environ
+from sys import platform
 from cffi import FFI
 from mip.model import Model, Solver, Column, Var, LinExpr, Constr, \
     VConstrList, VVarList
@@ -17,9 +18,13 @@
     lib_path = None
 
     if 'GUROBI_HOME' in environ:
-        libfile = glob(os.path.join(os.environ['GUROBI_HOME'],
-                                    'lib/libgurobi[0-9][0-9].*'))
-
+        if platform.lower().startswith('win'):
+            libfile = glob(os.path.join(os.environ['GUROBI_HOME'],
+                                        'bin\gurobi[0-9][0-9].dll'))
+        else:
+            libfile = glob(os.path.join(os.environ['GUROBI_HOME'],
+                                        'lib/libgurobi[0-9][0-9].*'))
+        
         if libfile:
             lib_path = libfile[0]