def DefaultExtension(schema_obj, form_obj, schemata=None):
    """Create a default field"""
    if schemata is None:
        schemata = ['systemconfig', 'profile', 'client']
    DefaultExtends = {'schema': {'properties/modules': [schema_obj]},
        'form': {'modules': {'items/': form_obj}}}
    output = {}
    for schema in schemata:
        output[schema] = DefaultExtends
    return output
