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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_flavor_ref(self, flavor):
 """ Flavors are odd in that the API expects an href link, not an ID, as with nearly every other resource. This method takes either a CloudDatabaseFlavor object, a flavor ID, a RAM size, or a flavor name, and uses that to determine the appropriate href. """

        flavor_obj = None
        if isinstance(flavor, CloudDatabaseFlavor):
            flavor_obj = flavor
        elif isinstance(flavor, int):
            # They passed an ID or a size
            try:
                flavor_obj = self.get_flavor(flavor)
            except exc.NotFound:
                # Must be either a size or bad ID, which will
                # be handled below
                pass
        if flavor_obj is None:
            # Try flavor name
            flavors = self.list_flavors()
            try:
                flavor_obj = [flav for flav in flavors
                        if flav.name == flavor][0]
            except IndexError:
                # No such name; try matching RAM
                try:
                    flavor_obj = [flav for flav in flavors
                            if flav.ram == flavor][0]
                except IndexError:
                    raise exc.FlavorNotFound("Could not determine flavor from "
                            "'%s'." % flavor)
        # OK, we have a Flavor object. Get the href
        href = [link["href"] for link in flavor_obj.links
                if link["rel"] == "self"][0]
        return href