class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.t: J = None
        self.u: B = None
        self.v: H = None
        self.p: I = None
        self.y: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.x: A = None
        self.o: E = None
        self.t: D = None
        self.z: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.s: B = None
        self.x: F = None
        self.p: B = None
        self.u: I = None
        self.r: D = None
        self.z: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.s: G = None
        self.o: J = None
        self.r: A = None
        self.y: A = None
        self.x: A = None
        self.u: I = None
        self.z: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: D = None
        self.q: C = None
        self.r: C = None
        self.x: F = None
        self.s: C = None
        self.y: E = None
        self.w: A = None
        self.t: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

e = A("e")
d = B("d")
j = C("j")
k = D("k")
c = E("c")
b = F("b")
g = G("g")
f = H("f")
m = I("m")
a = J("a")

e.o = g
e.t = a
e.u = d
e.v = f
e.p = m
e.y = k
d.z = j
d.y = m
d.o = g
j.u = c
j.o = c
j.x = e
j.t = k
j.z = f
k.w = j
c.q = m
c.u = m
c.s = d
c.p = d
c.x = b
c.r = k
c.z = k
b.p = c
b.s = g
b.z = g
b.o = a
b.r = e
b.y = e
b.x = e
b.u = m
g.p = j
g.q = j
g.r = j
g.s = j
g.o = k
g.x = b
g.y = c
g.w = e
g.t = a
f.t = d
f.s = d
f.x = c
m.y = j
m.r = j
m.o = d
m.x = k
m.p = b
m.u = e
a.t = d
assert b.z.o.w.u.x.y.o.o.txt == "
class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.t: J = None
        self.u: B = None
        self.v: H = None
        self.p: I = None
        self.y: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.x: A = None
        self.o: E = None
        self.t: D = None
        self.z: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.s: B = None
        self.x: F = None
        self.p: B = None
        self.u: I = None
        self.r: D = None
        self.z: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.s: G = None
        self.o: J = None
        self.r: A = None
        self.y: A = None
        self.x: A = None
        self.u: I = None
        self.z: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: D = None
        self.q: C = None
        self.r: C = None
        self.x: F = None
        self.s: C = None
        self.y: E = None
        self.w: A = None
        self.t: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

e = A("e")
d = B("d")
j = C("j")
k = D("k")
c = E("c")
b = F("b")
g = G("g")
f = H("f")
m = I("m")
a = J("a")

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