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

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.w: E = None
        self.v: A = None
        self.y: G = None
        self.o: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: A = None
        self.w: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: H = None
        self.v: F = None
        self.y: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.w: E = None
        self.v: A = None
        self.y: G = None
        self.o: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: A = None
        self.w: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: H = None
        self.v: F = None
        self.y: G = None
        self.txt = txt

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

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