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

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.s: B = None
        self.v: F = None
        self.t: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: G = None
        self.o: F = None
        self.w: B = None
        self.u: D = None
        self.t: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.y: G = None
        self.q: H = None
        self.v: E = None
        self.s: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.s: D = None
        self.o: A = None
        self.u: D = None
        self.p: G = None
        self.y: G = None
        self.txt = txt

h = A("h")
e = B("e")
j = C("j")
b = D("b")
i = E("i")
l = F("l")
a = G("a")
c = H("c")
m = C("m")
d = B("d")

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

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.s: B = None
        self.v: F = None
        self.t: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: G = None
        self.o: F = None
        self.w: B = None
        self.u: D = None
        self.t: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.y: G = None
        self.q: H = None
        self.v: E = None
        self.s: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.s: D = None
        self.o: A = None
        self.u: D = None
        self.p: G = None
        self.y: G = None
        self.txt = txt

h = A("h")
e = B("e")
j = C("j")
b = D("b")
i = E("i")
l = F("l")
a = G("a")
c = H("c")
m = C("m")
d = B("d")

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