Rename env var and change output to make it clear it's coming from DISPATCH

Author: chriso

README.md

@@ -214,7 +214,7 @@ serializable. That is, users should avoid using variables inside
 coroutines that cannot be pickled.
 
 If a pickle error is encountered, serialization tracing can be enabled
-with the `DURABLE_TRACE=1` environment variable to debug the issue. The
+with the `DISPATCH_TRACE=1` environment variable to debug the issue. The
 stacks of coroutines and generators will be printed to stdout before
 the pickle library attempts serialization.
 

src/dispatch/experimental/durable/function.py

@@ -14,7 +14,7 @@
 from . import frame as ext
 from .registry import RegisteredFunction, lookup_function, register_function
 
-TRACE = os.getenv("DURABLE_TRACE", False)
+TRACE = os.getenv("DISPATCH_TRACE", False)
 
 FRAME_CLEARED = 4
 
@@ -114,7 +114,7 @@ def __getstate__(self):
             ip, sp, stack = None, None, None
 
         if TRACE:
-            print(f"\n[DURABLE] Serializing {self}:")
+            print(f"\n[DISPATCH] Serializing {self}:")
             print(f"function = {rfn.fn.__qualname__} ({rfn.filename}:{rfn.lineno})")
             print(f"code hash = {rfn.hash}")
             print(f"args = {self.args}")