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

def get_call_target(self, callsite_addr):

    if (callsite_addr in self._call_sites):
        return self._call_sites[callsite_addr][0]
    return None
