def union_defs(self, defs, redefined):
        """Union with the given defs dictionary. This is meant to handle
        branch join-point, where a variable may have been defined in more
        than one branches.
        """
        for k, v in defs.items():
            if v > 0:
                self.define(k, redefined)
Union with the given defs dictionary. This is meant to handle
        branch join-point, where a variable may have been defined in more
        than one branches.
        
numba/parfors/array_analysis.py