Could not find a version that satisfies the requirement Flask pip install -U Flask
Collecting Flask Could not fetch URL https://pypi.python.org/simple/flask/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:590) - skipping
Could not find a version that satisfies the requirement Flask (from versions: )
No matching distribution found for Flask