Remove url slicing

Author: todorDim

mailjet_rest/client.py

@@ -23,7 +23,6 @@ def __init__(self, version=None, api_url=None):
         self.api_url = api_url or self.DEFAULT_API_URL
 
     def __getitem__(self, key):
-        url = self.api_url[0:]
         # Append version to URL.
         # Forward slash is ignored if present in self.version.
         url = urljoin(url, self.version + '/')