fix imports

Author: Jonathan Esterhazy

src/container_support/environment.py

@@ -24,7 +24,6 @@
 import pkg_resources
 
 import container_support as cs
-from container_support import serving
 
 logger = logging.getLogger(__name__)
 
@@ -317,7 +316,7 @@ def __init__(self, base_dir=ContainerEnvironment.BASE_DIRECTORY):
         self.port_range = os.environ.get(ContainerEnvironment.SAGEMAKER_SAFE_PORT_RANGE_ENV, None)
 
         self.default_accept = os.environ.get(HostingEnvironment.DEFAULT_INVOCATIONS_ACCEPT_ENV,
-                                             serving.JSON_CONTENT_TYPE)
+                                             cs.serving.JSON_CONTENT_TYPE)
 
         self.model_server_workers = int(os.environ.get(
             HostingEnvironment.MODEL_SERVER_WORKERS_PARAM,