class A:
    def __init__(self, txt: str):
        self.p: J = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: J = None
        self.q: A = None
        self.x: H = None
        self.o: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.z: F = None
        self.o: C = None
        self.q: C = None
        self.s: I = None
        self.x: B = None
        self.t: J = None
        self.p: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.q: H = None
        self.t: H = None
        self.v: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: J = None
        self.z: H = None
        self.v: C = None
        self.u: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: G = None
        self.u: G = None
        self.w: F = None
        self.z: H = None
        self.s: J = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: J = None
        self.q: A = None
        self.x: H = None
        self.o: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.z: F = None
        self.o: C = None
        self.q: C = None
        self.s: I = None
        self.x: B = None
        self.t: J = None
        self.p: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.q: H = None
        self.t: H = None
        self.v: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: J = None
        self.z: H = None
        self.v: C = None
        self.u: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: G = None
        self.u: G = None
        self.w: F = None
        self.z: H = None
        self.s: J = None
        self.txt = txt

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

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

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