class A:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: G = None
        self.p: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.x: E = None
        self.t: G = None
        self.v: D = None
        self.z: G = None
        self.p: H = None
        self.y: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.z: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: B = None
        self.u: D = None
        self.w: G = None
        self.z: F = None
        self.q: G = None
        self.x: A = None
        self.t: D = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.z: F = None
        self.t: C = None
        self.p: F = None
        self.r: D = None
        self.o: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: H = None
        self.v: H = None
        self.txt = txt

d = A("d")
n = B("n")
i = C("i")
f = D("f")
l = E("l")
k = F("k")
b = G("b")
c = H("c")
j = H("j")

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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.x: E = None
        self.t: G = None
        self.v: D = None
        self.z: G = None
        self.p: H = None
        self.y: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.z: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: B = None
        self.u: D = None
        self.w: G = None
        self.z: F = None
        self.q: G = None
        self.x: A = None
        self.t: D = None
        self.o: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.z: F = None
        self.t: C = None
        self.p: F = None
        self.r: D = None
        self.o: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: H = None
        self.v: H = None
        self.txt = txt

d = A("d")
n = B("n")
i = C("i")
f = D("f")
l = E("l")
k = F("k")
b = G("b")
c = H("c")
j = H("j")

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