def select_type(pathways, stype):
    """Selects all pathways of a given type
    
    Parameters
    ----------
    
    pathways : list
        List of pathways to be analyzed
        
    stype : str
        Type of the pathways to be selected. 
        Possible values are "REPH", "NONR".
        
    """
    di = dict(REPH='R', NONR='NR')
    selected = []
    for pw in pathways:
        if pw.pathway_type == di[stype]:
            selected.append(pw)
    return selected
