C-h f equivalent

[Skip Montanaro]

    Gerhard> Check out the help and dir builtin functions.
    ...
    Gerhard> There may be a shortcut that does just from Emacs' Python mode.

Sort of.  If you want to get the docs for something global-ish that you've
entered into the current Emacs buffer, hitting F1 will display the online
doc for the object under the cursor in another window.  Obviously, this
won't work with run-time objects such as class instances, but it does work
well with objects at the top level of importable modules,
e.g. string.find or sock.gethostbyaddr.

Skip