// A validator dedicated to the named line styles, based on the items in
// ls_mapper, and a list of possible strings read from Line2D.set_linestyle
_validate_named_linestyle = ValidateInStrings("linestyle",
list(six.iterkeys(ls_mapper)) +
list(six.itervalues(ls_mapper)) +
["None", "none", " ", ""],
ignorecase=True)