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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def lib_directories(self):
 """Get all "lib" directories."""

        if self._lib_directories is None:
            self._lib_directories = []
            app_path = os.getcwd()
            contents = os.listdir(app_path)
            for c in contents:
                # ensure content starts with lib, is directory, and is readable
                if c.startswith('lib') and os.path.isdir(c) and (os.access(c, os.R_OK)):
                    self._lib_directories.append(c)
        return sorted(self._lib_directories, reverse=True)