Adapt documentation for `copyright` and `credits` to reality. Previously, the documentation implied that all each of `copyright`,
`credits`, and `license`, would print a message to call the object in order to see the full text. In reality, only `license` exhibits this
behaviour, and `copyright` and `credit` print their full text either when printed, displayed, or called.
specified exit code.
.. data:: copyright
- license
credits
- Objects that when printed, print a message like "Type license() to see the
- full license text", and when called, display the corresponding text in a
+ Objects that when printed or called, print the text of copyright or
+ credits, respectively.
+
+.. data:: license
+
+ Object that when printed, prints the message "Type license() to see the
+ full license text", and when called, displays the full license text in a
pager-like fashion (one screen at a time).