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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _call_to(self, from_node, to_func, ret_node, stmt_idx=None, ins_addr=None, return_to_outside=False):
 """ Registers an edge between the caller basic block and callee function. :param from_addr: The basic block that control flow leaves during the transition. :type from_addr: angr.knowledge.CodeNode :param to_func: The function that we are calling :type to_func: Function :param ret_node The basic block that control flow should return to after the function call. :type to_func: angr.knowledge.CodeNode or None :param stmt_idx: Statement ID of this call. :type stmt_idx: int, str or None :param ins_addr: Instruction address of this call. :type ins_addr: int or None """


        self._register_nodes(True, from_node)

        if to_func.is_syscall:
            self.transition_graph.add_edge(from_node, to_func, type='syscall', stmt_idx=stmt_idx, ins_addr=ins_addr)
        else:
            self.transition_graph.add_edge(from_node, to_func, type='call', stmt_idx=stmt_idx, ins_addr=ins_addr)
            if ret_node is not None:
                self._fakeret_to(from_node, ret_node, to_outside=return_to_outside)

        self._local_transition_graph = None