class A:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: F = None
        self.p: F = None
        self.y: F = None
        self.o: F = None
        self.z: F = None
        self.r: E = None
        self.w: H = None
        self.u: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: F = None
        self.y: I = None
        self.q: H = None
        self.p: F = None
        self.s: F = None
        self.t: D = None
        self.v: H = None
        self.u: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: I = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: F = None
        self.y: I = None
        self.q: H = None
        self.p: F = None
        self.s: F = None
        self.t: D = None
        self.v: H = None
        self.u: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

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