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

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

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.r: I = None
        self.y: F = None
        self.w: E = None
        self.o: C = None
        self.x: I = None
        self.z: A = None
        self.p: I = None
        self.q: C = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.r: I = None
        self.y: F = None
        self.w: E = None
        self.o: C = None
        self.x: I = None
        self.z: A = None
        self.p: I = None
        self.q: C = None
        self.txt = txt

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

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

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

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

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

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

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