class A:
    def __init__(self, txt: str):
        self.u: I = None
        self.z: A = None
        self.q: B = None
        self.y: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.u: I = None
        self.w: I = None
        self.z: A = None
        self.y: I = None
        self.x: A = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.v: A = None
        self.z: G = None
        self.s: F = None
        self.u: G = None
        self.t: A = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.u: I = None
        self.w: I = None
        self.z: A = None
        self.y: I = None
        self.x: A = None
        self.txt = txt

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

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.v: A = None
        self.z: G = None
        self.s: F = None
        self.u: G = None
        self.t: A = None
        self.txt = txt

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

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

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