class A:
    def __init__(self, txt: str):
        self.u: B = None
        self.q: G = None
        self.t: H = None
        self.v: I = None
        self.r: H = None
        self.p: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: E = None
        self.t: J = None
        self.y: B = None
        self.v: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.w: H = None
        self.t: I = None
        self.v: A = None
        self.y: D = None
        self.o: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.p: C = None
        self.o: J = None
        self.u: C = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.x: A = None
        self.r: C = None
        self.o: D = None
        self.s: D = None
        self.v: B = None
        self.w: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: F = None
        self.p: B = None
        self.t: G = None
        self.o: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: D = None
        self.v: D = None
        self.z: E = None
        self.o: E = None
        self.w: E = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: E = None
        self.t: J = None
        self.y: B = None
        self.v: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.w: H = None
        self.t: I = None
        self.v: A = None
        self.y: D = None
        self.o: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.p: C = None
        self.o: J = None
        self.u: C = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.x: A = None
        self.r: C = None
        self.o: D = None
        self.s: D = None
        self.v: B = None
        self.w: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: F = None
        self.p: B = None
        self.t: G = None
        self.o: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: D = None
        self.v: D = None
        self.z: E = None
        self.o: E = None
        self.w: E = None
        self.txt = txt

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

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