class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: B = None
        self.p: B = None
        self.x: E = None
        self.t: F = None
        self.v: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.t: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: B = None
        self.v: I = None
        self.z: G = None
        self.p: B = None
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.s: B = None
        self.z: A = None
        self.r: F = None
        self.w: E = None
        self.v: B = None
        self.y: E = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.t: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.y: B = None
        self.v: I = None
        self.z: G = None
        self.p: B = None
        self.x: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.s: B = None
        self.z: A = None
        self.r: F = None
        self.w: E = None
        self.v: B = None
        self.y: E = None
        self.txt = txt

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

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