用pip安裝tornado庫:
python -m pip install tornado
出現問題一: Could not fetch URL https://pypi.org/simple/twisted/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/twisted/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.")) - skipping

解決辦法:python -m pip install tornado --trusted-host=pypi.python.org --trusted-host=pypi.org --trusted-host=files.pythonhosted.org
即在庫名后+ --trusted-host=pypi.python.org --trusted-host=pypi.org --trusted-host=files.pythonhosted.org
出現問題二:pip._vendor.urllib3.exceptions.ReadTimeoutError: HTTPSConnectionPool(host='files.pythonhosted.org', port=443): Read timed out.

解決辦法:python -m pip install --default-timeout=100 tornado --trusted-host=pypi.python.org --trusted-host=pypi.org --trusted-host=files.pythonhosted.org
