def METHOD_NAME(self, start, end) -> Set[XRef]:
    """
    Get a set of XRef objects that originate at a given address region
    bounded by start and end.  Useful for finding references from a basic block or function.
    """
    def f(x):
        return isinstance(x, int) and start <= x <= end
    addrs = filter(f, self.xrefs_by_ins_addr.keys())
    refs = set()
    for addr in addrs:
        refs = refs.union(self.xrefs_by_ins_addr[addr])
    return refs