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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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