Feature request: visual selection a range and perform debug_print_var

[xzbdmw]

And it will insert print below every variable inside the visual selection range

[TheLeoP]

The current behavior of debug_print_var is to debug print everything visually selected. This allows users to debug print expressions, not only variables.

A PR adding this feature would be welcome. It wouldn't need to modify debug_print_var, but add a new function for this instead.