Visualization and simulation of Intelligent Transportation Systems (ITS) for future city models is a key research area to bring better traffic safety and efficiency solutions in smart cities. However, the cost of deploying large-scale testbeds to analyze the performance of these solutions is prohibitively huge. Therefore, cooperative ITS simulation platforms are essential to test the performance of such solutions before their actual deployment. In order to fulfill this requirement we have developed PySNS3 (a Python-based framework for bidirectional coupling between NS3 and SUMO). To test the robustness and reliability of proposed framework we have compared its mobility as well as communication related simulation results with state-of-the-art NS2-mobility-model. We have performed a simulation scenario of Harbin city that includes evaluation of 802.11p MAC/PHY characteristics, the architecture of Wireless Access in Vehicular Environment (WAVE), and prediction of the vehicular Edge computation capacity. We have also performed the evaluation of a traffic efficiency application using proposed framework to reduce the fuel consumption and waiting time. The simulation results proved that the proposed framework can offer dynamic coupling between SUMO and NS3 for the evaluation of Edge computing solutions of ITS for future city models.