class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.t: H = None
        self.r: H = None
        self.o: B = None
        self.z: J = None
        self.p: B = None
        self.s: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: J = None
        self.z: G = None
        self.v: H = None
        self.w: D = None
        self.r: H = None
        self.o: J = None
        self.u: H = None
        self.s: D = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: G = None
        self.w: A = None
        self.r: C = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.y: J = None
        self.z: G = None
        self.v: H = None
        self.w: D = None
        self.r: H = None
        self.o: J = None
        self.u: H = None
        self.s: D = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: G = None
        self.w: A = None
        self.r: C = None
        self.txt = txt

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

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

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

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

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

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