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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: A = None
        self.y: C = None
        self.z: H = None
        self.v: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: G = None
        self.z: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.z: A = None
        self.s: F = None
        self.t: A = None
        self.w: B = None
        self.u: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: C = None
        self.u: G = None
        self.r: C = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: G = None
        self.z: D = None
        self.s: C = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.t: A = None
        self.y: C = None
        self.z: H = None
        self.v: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: C = None
        self.u: G = None
        self.z: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: B = None
        self.z: A = None
        self.s: F = None
        self.t: A = None
        self.w: B = None
        self.u: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: C = None
        self.u: G = None
        self.r: C = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: G = None
        self.z: D = None
        self.s: C = None
        self.r: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

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

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