(find-keyword name) (find-keyword ns name)
Returns a Keyword with the given namespace and name if one already exists. This function will not intern a new keyword. If the keyword has not already been interned, it will return nil. Do not use : in the keyword strings, it will be added automatically.
user=> (find-keyword "a")
nil
user=> :a
:a
user=> (find-keyword "a")
:a