<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def resolve_font(name):
 """Turns font names into absolute filenames This is case sensitive. The extension should be omitted. For example:: Absolute paths are allowed:: True Raises :exc:`FontNotFound` on failure:: """

    if os.path.exists(name):
        return os.path.abspath(name)
    fonts = get_font_files()
    if name in fonts:
        return fonts[name]
    raise FontNotFound("Can't find %r :'(  Try adding it to ~/.fonts" % name)