MPRestError: HTTPSConnectionPool

Hi, I got an error when trying this example.http://matgenb.materialsvirtuallab.org/2016/09/08/Data-driven-First-Principles-Methods-for-the-Study-and-Design-of-Alkali-Superionic-Conductors-Part-2-Phase-and-Electrochemical-Stability.html Here is the code:

rester = MPRester(api_key="**********************")
mp_entries = rester.get_entries_in_chemsys(["Li", "P", "S", "Cl"])

And the error is:

MPRestError: HTTPSConnectionPool(host='materialsproject.org', port=443): Max retries exceeded with url: /rest/v2/query (Caused by SSLError(SSLError("bad handshake: SysCallError(54, 'ECONNRESET')")))

Can anyone help me with this problem?