STYLE: Miscellaneous clean-up

[jhlegarreta]

• STYLE: Prefer obtaining the filename automatically from Python
• DOC: Fix script debug trace description
• STYLE: Remove macOS-specific ipython shebang
• STYLE: Remove duplicate Python shebang
• STYLE: Remove unnecessay std output print at package import
• STYLE: Remove whitespaces on empty lines

[jhlegarreta]

All these print statements should be managed by a logger, which would take care of printing the appropriate module/filename. Left for future work.