oops update the check to work for the older version of netcdf4

Author: kafitzgerald

src/wrf/util.py

@@ -9,6 +9,7 @@
 from types import GeneratorType
 import datetime as dt
 from inspect import getmodule
+from netCDF4 import Dataset
 
 try:
     from inspect import signature
@@ -134,10 +135,11 @@ def is_multi_file(wrfin):
         is a single NetCDF file object.
 
     """
-    try:
-        iter(wrfin)
+    if isinstance(wrfin, Dataset):
+        is_iterable = False
+    elif isinstance(wrfin, Iterable):
         is_iterable = True
-    except Exception:
+    else:
         is_iterable = False
 
     return (is_iterable and not isstr(wrfin))