def _Global(self, t):
        self.fill("global ")
        interleave(lambda: self.write(", "), self.write, t.names)
    def _Nonlocal(self, t):
        self.fill("nonlocal ")
        interleave(lambda: self.write(", "), self.write, t.names)
    def _Await(self, t):
        self.write("(")
        self.write("await")
        if t.value:
            self.write(" ")
            self.dispatch(t.value)
        self.write(")")
    def _Yield(self, t):
        self.write("(")
        self.write("yield")
        if t.value:
            self.write(" ")
            self.dispatch(t.value)
        self.write(")")
    def _YieldFrom(self, t):
        self.write("(")
        self.write("yield from")
        if t.value:
            self.write(" ")
            self.dispatch(t.value)
        self.write(")")
    def _Raise(self, t):
        self.fill("raise")
        if not t.exc:
            assert not t.cause
            return
        self.write(" ")
        self.dispatch(t.exc)
        if t.cause:
            self.write(" from ")
            self.dispatch(t.cause)
    def _Try(self, t):
        self.fill("try")
        self.enter()
        self.dispatch(t.body)
        self.leave()
        for ex in t.handlers:
            self.dispatch(ex)
        if t.orelse:
            self.fill("else")
            self.enter()
            self.dispatch(t.orelse)
            self.leave()
        if t.finalbody:
            self.fill("finally")
            self.enter()
            self.dispatch(t.finalbody)
            self.leave()