Use importlib_metadata if importlib.metadata is not available.

catkit2/testbed/service_proxy.py

@@ -1,6 +1,10 @@
 from .. import catkit_bindings
 
-import importlib.metadata
+try:
+    import importlib.metadata as importlib_metadata
+except ImportError:
+    import importlib_metadata
+
 
 class ServiceProxy(catkit_bindings.ServiceProxy):
     '''A proxy for a service connected to a server.
@@ -103,7 +107,7 @@ def get_service_interface(cls, interface_name):
         if interface_name is None:
             return ServiceProxy
 
-        entry_point = importlib.metadata.entry_points(group='catkit2.proxies', name=interface_name)
+        entry_point = importlib_metadata.entry_points(group='catkit2.proxies', name=interface_name)
 
         if not entry_point:
             raise AttributeError(f"Service proxy class with interface name '{interface_name}' not found. Did you set it as an entry point?")

catkit2/testbed/testbed.py

@@ -19,6 +19,11 @@
 from ..proto import testbed_pb2 as testbed_proto
 from ..proto import service_pb2 as service_proto
 
+try:
+    import importlib.metadata as importlib_metadata
+except ImportError:
+    import importlib_metadata
+
 
 SERVICE_LIVELINESS = 5
 
@@ -273,7 +278,7 @@ def __init__(self, port, is_simulated, config):
 
         # Read in service types.
         self.service_type_paths = {}
-        for entry_point in importlib.metadata.entry_points(group="catkit2.services"):
+        for entry_point in importlib_metadata.entry_points(group="catkit2.services"):
             module = entry_point.module
             spec = importlib.util.find_spec(module)
             path = os.path.abspath(spec.origin)

environment.yml

@@ -37,6 +37,7 @@ dependencies:
   - networkx
   - pytest
   - flake8
+  - importlib_metadata
   - pip:
     - dcps
     - zwoasi>=0.0.21