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

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

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

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: E = None
        self.o: D = None
        self.y: H = None
        self.u: C = None
        self.w: B = None
        self.r: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: D = None
        self.o: H = None
        self.v: G = None
        self.x: E = None
        self.q: C = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.o: D = None
        self.y: C = None
        self.u: H = None
        self.v: I = None
        self.x: E = None
        self.q: B = None
        self.s: H = None
        self.z: E = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.z: G = None
        self.p: E = None
        self.o: D = None
        self.y: H = None
        self.u: C = None
        self.w: B = None
        self.r: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: D = None
        self.o: H = None
        self.v: G = None
        self.x: E = None
        self.q: C = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.o: D = None
        self.y: C = None
        self.u: H = None
        self.v: I = None
        self.x: E = None
        self.q: B = None
        self.s: H = None
        self.z: E = None
        self.txt = txt

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

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

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

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