class A:
    def __init__(self, txt: str):
        self.p: D = None
        self.t: B = None
        self.u: H = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: J = None
        self.v: E = None
        self.y: A = None
        self.w: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.x: H = None
        self.y: H = None
        self.w: D = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: F = None
        self.o: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.z: H = None
        self.p: B = None
        self.y: E = None
        self.q: B = None
        self.t: H = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: J = None
        self.v: E = None
        self.y: A = None
        self.w: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: I = None
        self.x: H = None
        self.y: H = None
        self.w: D = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: F = None
        self.o: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.z: H = None
        self.p: B = None
        self.y: E = None
        self.q: B = None
        self.t: H = None
        self.txt = txt

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

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