'Get the hypothetical return address of a call.
:param callsite_addr:       The address of the basic block that ends in a call.
:return:                    The likely return target of said call, or None if callsite_addr
is not a callsite.'

def get_call_return(self, callsite_addr):

    if (callsite_addr in self._call_sites):
        return self._call_sites[callsite_addr][1]
    return None
