def script_repr(val,imports,prefix,settings):
    """
    Variant of repr() designed for generating a runnable script.

    Instances of types that require special handling can use the
    script_repr_reg dictionary. Using the type as a key, add a
    function that returns a suitable representation of instances of
    that type, and adds the required import statement.

    The repr of a parameter can be suppressed by returning None from
    the appropriate hook in script_repr_reg.
    """
    return pprint(val,imports,prefix,settings,unknown_value=None,
                  qualify=True,separator="\n")