class A:
    def __init__(self, txt: str):
        self.s: G = None
        self.p: H = None
        self.o: F = None
        self.v: H = None
        self.w: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: I = None
        self.x: G = None
        self.q: B = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.r: H = None
        self.t: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.r: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: H = None
        self.t: J = None
        self.r: I = None
        self.z: E = None
        self.s: F = None
        self.p: D = None
        self.x: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: J = None
        self.o: I = None
        self.z: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: J = None
        self.o: C = None
        self.x: J = None
        self.r: A = None
        self.w: H = None
        self.v: F = None
        self.z: F = None
        self.s: J = None
        self.p: C = None
        self.y: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: I = None
        self.x: G = None
        self.q: B = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.r: H = None
        self.t: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: D = None
        self.r: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: H = None
        self.t: J = None
        self.r: I = None
        self.z: E = None
        self.s: F = None
        self.p: D = None
        self.x: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: J = None
        self.o: I = None
        self.z: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: J = None
        self.o: C = None
        self.x: J = None
        self.r: A = None
        self.w: H = None
        self.v: F = None
        self.z: F = None
        self.s: J = None
        self.p: C = None
        self.y: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: D = None
        self.txt = txt

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

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