Name 'cbclib' is not defined

**Describe the bug**

I cannot solve even a very simple program, because the system claims that `cbclib` is not defined:

```
Traceback (most recent call last):
File "test_mip.py", line 2, in
m = Model("test", solver_name=CBC)
File "local-packages\Python310\site-packages\mip\model.py", line 87, in __init__
import mip.cbc
File "local-packages\Python310\site-packages\mip\cbc.py", line 603, in
Osi_getNumCols = cbclib.Osi_getNumCols
NameError: name 'cbclib' is not defined
```

**To Reproduce**

```
from mip import Model, CBC
m = Model("test", solver_name=CBC)
```

**Expected behavior**
No error.

**Desktop (please complete the following information):**
- Windows 11 22H2
- Python version: 3.10.10
- Python-MIP version (we recommend you to test with the latest version): 1.15.0 (also exists in 1.14.0)