@pimms.param<EOL><INDENT>def cache_path(cp):<DEDENT>
if cp is None: return None<EOL>cp = os.path.expanduser(os.path.expandvars(cp))<EOL>if not os.path.isdir(cp): raise ValueError('<STR_LIT>')<EOL>return cp<EOL>
filemap.cache_path is the path into which the filemap's data are cached (if necessary). This
parameter represents the provided cache_path argument, but may not be the actual used cache
path, which can be found in the actual_cache_path member.