fix: load_model fallback to BytesIO for Py3.6

Catch io.UnsupportedOperation raised in Python <3.7 and buffer file
contents into a BytesIO to work around the error.

pytorch_tabnet/tab_model.py

@@ -13,6 +13,7 @@
 from sklearn.base import BaseEstimator
 from torch.utils.data import DataLoader
 from copy import deepcopy
+import io
 import json
 from pathlib import Path
 import shutil
@@ -305,7 +306,13 @@ def load_model(self, filepath):
                 with z.open("model_params.json") as f:
                     loaded_params = json.load(f)
                 with z.open("network.pt") as f:
-                    saved_state_dict = torch.load(f)
+                    try:
+                        saved_state_dict = torch.load(f)
+                    except io.UnsupportedOperation:
+                        # In Python <3.7, the returned file object is not seekable (which at least
+                        # some versions of PyTorch require) - so we'll try buffering it in to a
+                        # BytesIO instead:
+                        saved_state_dict = torch.load(io.BytesIO(f.read()))
         except KeyError:
             raise KeyError("Your zip file is missing at least one component")