remove private import of ddtrace functionality

Author: emmettbutler

datadog_lambda/wrapper.py

@@ -9,7 +9,6 @@
 from importlib import import_module
 from time import time_ns
 
-from ddtrace.internal._exceptions import BlockingException
 from datadog_lambda.extension import should_use_extension, flush_extension
 from datadog_lambda.cold_start import (
     set_cold_start,
@@ -191,16 +190,17 @@ def __call__(self, event, context, **kwargs):
             if self.blocking_response:
                 return self.blocking_response
             self.response = self.func(event, context, **kwargs)
-        except BlockingException:
-            self.blocking_response = get_asm_blocked_response(self.event_source)
-        except Exception:
-            from datadog_lambda.metric import submit_errors_metric
+        except Exception as e:
+            if type(e).__name__ == "BlockingException":
+                self.blocking_response = get_asm_blocked_response(self.event_source)
+            else:
+                from datadog_lambda.metric import submit_errors_metric
 
-            submit_errors_metric(context)
+                submit_errors_metric(context)
 
-            if self.span:
-                self.span.set_traceback()
-            raise
+                if self.span:
+                    self.span.set_traceback()
+                raise
         finally:
             self._after(event, context)
         if self.blocking_response: