'return an `Options` instance, either with the default options,
if ``s is None``, or with all options whose name or description
contains `s`, if `s` is a string (case is disregarded),
or with entries from dictionary `s` as options, not complemented
with default options or settings
Returns: see above.'

def __init__(self, s=None, unchecked=False):

    if (s is None):
        super(Options, self).__init__(Options.defaults())
    elif (type(s) is str):
        super(Options, self).__init__(Options().match(s))
    else:
        super(Options, self).__init__(s)
    if (not unchecked):
        for key in list(self.keys()):
            if (key not in Options.defaults()):
                print((('Warning    in    cma.Options.__init__():    invalid    key    ``' + str(key)) + '``    popped'))
                self.pop(key)
