Environment raspbian: jessie Linux phome 4.9.35-v7+ #1014 SMP Goal: To setup Jupyter Notebook. (needed pip3 18.1. (It required Python 3.5 but mine is 3.4.2) Conclusion: - Python-3.6.11 : OK - Python-3.8.3 make : OK, but pip cannot connect TLS/SSL ( https://stackoverflow.com/questions/62827291/warning-pip-is-configured-with-locations-that-require-tls-ssl-however-the-ssl ) I think that it occurred by the difference of openssl versions. (But I did not to try figure out) - Python-3.7.4 : Same problem like 3.8.3. - Python-3.5.9 : Compile error by gcov dependency. Method: - Download 3.6.11 source and compile. - Type "make altinstall" - Make file links with "update-alternatives" command.