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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_collections(self, ignore=None):
 """Return the collections matching the given `_ignore` value Parameters ignore : `bool`, or `None` value of `_ignore` to match Returns ------- collections : `list` if `ignore=None`, simply returns all collections, otherwise returns those collections matching the `ignore` parameter """

        if ignore is None:
            return self.collections
        return [c for c in self.collections if
                getattr(c, '_ignore', None) == ignore]