tree: Turn the output of str() into a tree diagram
Description
The super useful function str() uses .. to indicate the level
of sub-elements of an object, which may be difficult to read. This function
uses vertical pipes to connect all sub-elements on the same level, so it is
clearer which elements belong to the same parent element in an object with a
nested structure (such as a nested list).
Usage
tree(...)
Arguments
...
Arguments to be passed to str() (note that the
comp.str is hardcoded inside this function, and it is the only
argument that you cannot customize).