Adding lats and lons properties (#135)

Adding lats and lons properties for Grib2Message objects.

Cleanup of imports

This commit refernces issue #114

Co-authored-by: Eric Engle <EricEngle-NOAA@users.noreply.github.com>

grib2io/_grib2io.py

@@ -21,24 +21,22 @@
 * [Plotting Arakawa Rotated Lat/Lon Grids](https://github.com/NOAA-MDL/grib2io/blob/master/demos/plot-arakawa-rotlatlon-grids.ipynb)
 """
 
+from dataclasses import dataclass, field
+from numpy.typing import NDArray
+from typing import Union, Optional
 import builtins
 import collections
 import copy
 import datetime
 import hashlib
+import numpy as np
 import os
+import pyproj
 import re
 import struct
 import sys
-from typing import Union, Optional
 import warnings
 
-from dataclasses import dataclass, field
-from numpy import ma
-import numpy as np
-from numpy.typing import NDArray
-import pyproj
-
 from . import g2clib
 from . import tables
 from . import templates
@@ -725,6 +723,18 @@ def griddef(self):
         return Grib2GridDef.from_section3(self.section3)
 
 
+    @property
+    def lats(self):
+        """Return grid latitudes."""
+        return self.latlons()[0]
+
+
+    @property
+    def lons(self):
+        """Return grid longitudes."""
+        return self.latlons()[1]
+
+
     def __repr__(self):
         """
         Return an unambiguous string representation of the object.