class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.y: A = None
        self.o: D = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.t: D = None
        self.u: B = None
        self.w: E = None
        self.x: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.r: B = None
        self.u: G = None
        self.q: G = None
        self.v: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: F = None
        self.v: D = None
        self.y: A = None
        self.q: A = None
        self.s: F = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: G = None
        self.o: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: B = None
        self.x: F = None
        self.s: D = None
        self.u: B = None
        self.p: C = None
        self.txt = txt

b = A("b")
e = B("e")
m = C("m")
j = D("j")
l = E("l")
i = F("i")
f = G("f")
n = D("n")
k = A("k")

b.t = e
b.y = k
b.o = n
b.s = l
e.u = k
e.x = b
m.s = e
m.u = e
m.t = n
m.w = l
m.x = l
j.s = e
j.r = e
j.u = f
j.q = f
j.v = m
l.u = j
l.v = j
l.p = j
l.r = i
l.s = i
l.y = k
l.q = b
i.p = f
i.w = f
i.o = e
f.r = l
f.q = e
f.u = e
f.x = i
f.s = n
f.p = m
n.s = e
n.r = e
n.u = f
n.q = f
n.v = m
k.t = e
k.y = b
k.o = n
k.s = l
assert m.w.q.o.v.t.u.q.txt == "
class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.y: A = None
        self.o: D = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.t: D = None
        self.u: B = None
        self.w: E = None
        self.x: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.r: B = None
        self.u: G = None
        self.q: G = None
        self.v: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: F = None
        self.v: D = None
        self.y: A = None
        self.q: A = None
        self.s: F = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.w: G = None
        self.o: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: B = None
        self.x: F = None
        self.s: D = None
        self.u: B = None
        self.p: C = None
        self.txt = txt

b = A("b")
e = B("e")
m = C("m")
j = D("j")
l = E("l")
i = F("i")
f = G("f")
n = D("n")
k = A("k")

b.t = e
b.y = k
b.o = n
b.s = l
e.u = k
e.x = b
m.s = e
m.u = e
m.t = n
m.w = l
m.x = l
j.s = e
j.r = e
j.u = f
j.q = f
j.v = m
l.u = j
l.v = j
l.p = j
l.r = i
l.s = i
l.y = k
l.q = b
i.p = f
i.w = f
i.o = e
f.r = l
f.q = e
f.u = e
f.x = i
f.s = n
f.p = m
n.s = e
n.r = e
n.u = f
n.q = f
n.v = m
k.t = e
k.y = b
k.o = n
k.s = l
assert m.w.q.o.v.t.u.q.txt == "e"