class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.q: C = None
        self.o: I = None
        self.t: I = None
        self.r: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.r: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: D = None
        self.q: D = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.o: C = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: C = None
        self.p: F = None
        self.r: F = None
        self.u: C = None
        self.q: H = None
        self.z: F = None
        self.t: F = None
        self.o: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: E = None
        self.z: E = None
        self.y: A = None
        self.x: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.r: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: D = None
        self.q: D = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.o: C = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: C = None
        self.x: C = None
        self.p: F = None
        self.r: F = None
        self.u: C = None
        self.q: H = None
        self.z: F = None
        self.t: F = None
        self.o: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: E = None
        self.z: E = None
        self.y: A = None
        self.x: I = None
        self.txt = txt

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

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

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