class A:
    def __init__(self, txt: str):
        self.y: D = None
        self.u: G = None
        self.r: B = None
        self.o: H = None
        self.v: C = None
        self.s: E = None
        self.z: B = None
        self.p: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.z: I = None
        self.t: F = None
        self.y: F = None
        self.r: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.q: I = None
        self.o: F = None
        self.p: F = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: J = None
        self.x: A = None
        self.o: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: I = None
        self.x: J = None
        self.p: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: C = None
        self.s: F = None
        self.p: F = None
        self.u: B = None
        self.z: B = None
        self.r: J = None
        self.v: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.w: B = None
        self.s: C = None
        self.v: H = None
        self.t: C = None
        self.o: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.s: B = None
        self.p: E = None
        self.z: C = None
        self.w: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.z: I = None
        self.t: F = None
        self.y: F = None
        self.r: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.q: I = None
        self.o: F = None
        self.p: F = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: J = None
        self.x: A = None
        self.o: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: I = None
        self.x: J = None
        self.p: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: C = None
        self.s: F = None
        self.p: F = None
        self.u: B = None
        self.z: B = None
        self.r: J = None
        self.v: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.w: B = None
        self.s: C = None
        self.v: H = None
        self.t: C = None
        self.o: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.s: B = None
        self.p: E = None
        self.z: C = None
        self.w: H = None
        self.txt = txt

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

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