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

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

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

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

class E:
    def __init__(self, txt: str):
        self.s: F = None
        self.t: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: J = None
        self.w: D = None
        self.y: I = None
        self.o: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: C = None
        self.s: I = None
        self.o: B = None
        self.r: A = None
        self.u: I = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.u: F = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.s: F = None
        self.t: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: J = None
        self.w: D = None
        self.y: I = None
        self.o: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: C = None
        self.s: I = None
        self.o: B = None
        self.r: A = None
        self.u: I = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.z: J = None
        self.u: F = None
        self.txt = txt

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

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

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