distributed: Import inspect only during DC file read

Closes #1336

direct/src/distributed/ConnectionRepository.py

@@ -7,7 +7,6 @@ from direct.distributed.DoCollectionManager import DoCollectionManager
 from direct.showbase import GarbageReport
 from .PyDatagramIterator import PyDatagramIterator
 
-import inspect
 import gc
 
 __all__ = ["ConnectionRepository", "GCTrigger"]
@@ -309,6 +308,8 @@ class ConnectionRepository(
 
         # Now get the class definition for the classes named in the DC
         # file.
+        import inspect
+
         for i in range(dcFile.getNumClasses()):
             dclass = dcFile.getClass(i)
             number = dclass.getNumber()