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

class B:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: B = None
        self.q: G = None
        self.y: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: G = None
        self.o: F = None
        self.x: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: I = None
        self.r: B = None
        self.t: G = None
        self.v: A = None
        self.x: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.x: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: B = None
        self.q: G = None
        self.y: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: G = None
        self.o: F = None
        self.x: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: I = None
        self.r: B = None
        self.t: G = None
        self.v: A = None
        self.x: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.x: E = None
        self.txt = txt

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

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