class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.w: G = None
        self.y: E = None
        self.u: D = None
        self.p: B = None
        self.r: F = None
        self.s: E = None
        self.v: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: I = None
        self.s: B = None
        self.o: B = None
        self.r: H = None
        self.p: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: H = None
        self.x: C = None
        self.t: G = None
        self.y: A = None
        self.u: C = None
        self.s: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.u: E = None
        self.v: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: G = None
        self.t: B = None
        self.u: B = None
        self.v: C = None
        self.r: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: E = None
        self.p: E = None
        self.o: G = None
        self.x: B = None
        self.txt = txt

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

k.t = b
k.u = b
k.w = l
k.y = d
k.s = d
k.p = i
k.r = f
k.v = a
i.w = d
i.o = a
a.w = j
a.v = l
b.t = j
b.p = j
b.s = i
b.o = i
b.r = m
d.p = m
d.x = a
d.u = a
d.s = a
d.t = l
d.y = k
c.s = a
c.u = d
c.v = i
l.r = k
l.z = j
l.w = i
m.s = b
m.r = b
m.o = l
m.t = i
m.u = i
m.v = a
j.t = a
j.u = d
j.p = d
j.o = l
j.x = i
f.s = a
f.u = d
f.v = i
assert f.u.y.u.t.o.r.txt == "
class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.w: G = None
        self.y: E = None
        self.u: D = None
        self.p: B = None
        self.r: F = None
        self.s: E = None
        self.v: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: I = None
        self.s: B = None
        self.o: B = None
        self.r: H = None
        self.p: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: H = None
        self.x: C = None
        self.t: G = None
        self.y: A = None
        self.u: C = None
        self.s: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.u: E = None
        self.v: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: G = None
        self.t: B = None
        self.u: B = None
        self.v: C = None
        self.r: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: E = None
        self.p: E = None
        self.o: G = None
        self.x: B = None
        self.txt = txt

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

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