class A:
    def __init__(self, txt: str):
        self.y: F = None
        self.p: A = None
        self.x: D = None
        self.z: A = None
        self.w: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: F = None
        self.x: D = None
        self.r: A = None
        self.w: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: G = None
        self.q: E = None
        self.x: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: B = None
        self.y: E = None
        self.x: H = None
        self.u: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.w: D = None
        self.t: G = None
        self.y: E = None
        self.p: D = None
        self.z: B = None
        self.txt = txt

e = A("e")
k = B("k")
j = C("j")
i = D("i")
n = E("n")
l = F("l")
g = G("g")
m = H("m")
a = C("a")
d = A("d")

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

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

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: F = None
        self.x: D = None
        self.r: A = None
        self.w: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: G = None
        self.q: E = None
        self.x: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: B = None
        self.y: E = None
        self.x: H = None
        self.u: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.w: D = None
        self.t: G = None
        self.y: E = None
        self.p: D = None
        self.z: B = None
        self.txt = txt

e = A("e")
k = B("k")
j = C("j")
i = D("i")
n = E("n")
l = F("l")
g = G("g")
m = H("m")
a = C("a")
d = A("d")

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