idanpa/calcpy ? reverse-engineered prompt

Build me a terminal calculator app that feels like using a smarter Python prompt, but with a cleaner, friendlier experience for everyday math and programmer stuff.

I want to be able to type expressions naturally, including implicit multiplication like 2x or (x+1)(x-1), and see both the exact symbolic answer and the numeric result. It should handle normal arithmetic, powers, fractions, bitwise ops, binary and hex, plus math functions like sin, diff, integrate, and solve. Please also support quick extras like currency conversion, date and time math, sizes like MB and KB, and unit prefixes. It would be great if it shows a live preview while typing, keeps my variables between sessions, lets me copy the last result easily, and gives useful help when I add a question mark to an expression. If you need to look up current docs online for any libraries, feel free to do that.