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

class B:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: E = None
        self.s: E = None
        self.x: E = None
        self.z: C = None
        self.t: G = None
        self.w: F = None
        self.y: H = None
        self.u: F = None
        self.p: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.u: C = None
        self.q: D = None
        self.o: D = None
        self.y: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: J = None
        self.v: B = None
        self.w: J = None
        self.r: E = None
        self.z: J = None
        self.u: H = None
        self.y: C = None
        self.s: A = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: E = None
        self.s: E = None
        self.x: E = None
        self.z: C = None
        self.t: G = None
        self.w: F = None
        self.y: H = None
        self.u: F = None
        self.p: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.u: C = None
        self.q: D = None
        self.o: D = None
        self.y: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.t: J = None
        self.v: B = None
        self.w: J = None
        self.r: E = None
        self.z: J = None
        self.u: H = None
        self.y: C = None
        self.s: A = None
        self.txt = txt

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

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

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