IMP connector_walmart Important change to authentication methods used by API

connector_walmart/components/api/exceptions.py

@@ -0,0 +1,21 @@
+class BaseException(Exception):
+    """
+    Base Exception which implements message attr on exceptions
+    Required for: Python 3
+    """
+    def __init__(self, message=None, *args, **kwargs):
+        self.message = message
+        super(BaseException, self).__init__(
+            self.message, *args, **kwargs
+        )
+
+    def __str__(self):
+        return self.message or self.__class__.__name__
+
+
+class WalmartException(BaseException):
+    pass
+
+
+class WalmartAuthenticationError(WalmartException):
+    pass