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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get(self, twig=None, check_visible=True, check_default=True, **kwargs):
 """ Get a single parameter from this ParameterSet. This works exactly the same as filter except there must be only a single result, and the Parameter itself is returned instead of a ParameterSet. Also see :meth:`get_parameter` (which is simply an alias of this method) :parameter str twig: (optional) the search twig - essentially a single string with any delimiter (ie '@') that will be parsed into any of the meta-tags. Example: instead of b.filter(context='component', component='starA'), you could do b.filter('starA@component'). :parameter bool check_visible: whether to hide invisible parameters. These are usually parameters that do not play a role unless the value of another parameter meets some condition. :parameter bool check_default: whether to exclude parameters which have a _default tag (these are parameters which solely exist to provide defaults for when new parameters or datasets are added and the parameter needs to be copied appropriately). Defaults to True. :parameter **kwargs: meta-tags to search (ie. 'context', 'component', 'model', etc). See :func:`meta` for all possible options. :return: the resulting :class:`Parameter` :raises ValueError: if either 0 or more than 1 results are found matching the search. """

        kwargs['check_visible'] = check_visible
        kwargs['check_default'] = check_default
        # print "***", kwargs
        ps = self.filter(twig=twig, **kwargs)
        if not len(ps):
            # TODO: custom exception?
            raise ValueError("0 results found")
        elif len(ps) != 1:
            # TODO: custom exception?
            raise ValueError("{} results found: {}".format(len(ps), ps.twigs))
        else:
            # then only 1 item, so return the parameter
            return ps._params[0]