Fixup

Author: hmstepanek

newrelic/core/transaction_node.py

@@ -620,11 +620,11 @@ def _add_call_count(source, target):
 
         return intrinsics
 
-    def span_protos(self, settings, ct_processing_time=0):
+    def span_protos(self, settings, ct_processing_time=None):
         for span in self.span_events(settings, attr_class=SpanProtoAttrs, ct_processing_time=ct_processing_time):
             yield Span(trace_id=self.trace_id, intrinsics=span[0], user_attributes=span[1], agent_attributes=span[2])
 
-    def span_events(self, settings, attr_class=dict, ct_processing_time=0):
+    def span_events(self, settings, attr_class=dict, ct_processing_time=None):
         base_attrs = attr_class(
             (
                 ("transactionId", self.guid),