adds line number to tracing tag of python functions to make them uniq…

…ue (#39)

lobster/tools/python/python.py

@@ -90,7 +90,11 @@ def fqn(self):
             rv = self.parent.fqn() + "."
         else:
             rv = ""
-        rv += self.name
+        if self.location.line is not None and \
+          isinstance(self, Python_Function):
+            rv += f"{self.name}:{str(self.location.line)}"
+        else:
+            rv += self.name
         return rv
 
     def lobster_tag(self):