def METHOD_NAME(self, ec):
    """
    Determine user module path extensions, if any. As typical users are not expected to have many local modules,
    further categorizing them using module classes is considered overkill. Thus, we are using a plain hierarchical
    scheme for user modules instead.
    Examples: Compiler/GCC/4.8.3 (for GCC/4.8.3 module), MPI/GCC/4.8.3/OpenMPI/1.6.5 (for OpenMPI/1.6.5 module)
    """
    # Use "system" module path extensions of hierarchical MNS (i.e., w/o module class)
    return super(CategorizedHMNS, self).det_modpath_extensions(ec)