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

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: D = None
        self.p: C = None
        self.t: D = None
        self.x: C = None
        self.u: D = None
        self.o: D = None
        self.s: C = None
        self.y: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: E = None
        self.t: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.t: C = None
        self.y: A = None
        self.w: C = None
        self.z: A = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.y: E = None
        self.w: E = None
        self.q: H = None
        self.r: B = None
        self.v: H = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: D = None
        self.p: C = None
        self.t: D = None
        self.x: C = None
        self.u: D = None
        self.o: D = None
        self.s: C = None
        self.y: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: A = None
        self.u: E = None
        self.t: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.t: C = None
        self.y: A = None
        self.w: C = None
        self.z: A = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.y: E = None
        self.w: E = None
        self.q: H = None
        self.r: B = None
        self.v: H = None
        self.txt = txt

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

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

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