class A:
    def __init__(self, txt: str):
        self.t: C = None
        self.p: F = None
        self.y: J = None
        self.w: H = None
        self.z: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: F = None
        self.o: B = None
        self.r: A = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.s: D = None
        self.q: B = None
        self.y: D = None
        self.z: E = None
        self.w: A = None
        self.u: B = None
        self.x: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.s: G = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: F = None
        self.o: B = None
        self.r: A = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.s: D = None
        self.q: B = None
        self.y: D = None
        self.z: E = None
        self.w: A = None
        self.u: B = None
        self.x: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.s: G = None
        self.txt = txt

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

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