Fix the previous error

jedi/api.py

@@ -391,7 +391,9 @@ class Script(object):
             defs, search_name = evaluate.goto(stmt)
             definitions = follow_inexistent_imports(defs)
             if isinstance(user_stmt, pr.Statement):
-                if user_stmt.get_commands()[0].start_pos > self.pos:
+                call = user_stmt.get_commands()[0]
+                if not isinstance(call, (str, unicode)) and \
+                   call.start_pos > self.pos:
                     # The cursor must be after the start, otherwise the
                     # statement is just an assignee.
                     definitions = [user_stmt]