'If we don\'t have any information about the caller, we have no way to get the address of the current function.
:param BlockID block_id: The block ID.
:return:                 The function address if there is one, or None if it\'s not possible to get.
:rtype:                  int or None'

@staticmethod
def _block_id_current_func_addr(block_id):

    if block_id.callsite_tuples:
        return block_id.callsite_tuples[(-1)]
    return None
