class A:
    def __init__(self, txt: str):
        self.x: B = None
        self.z: D = None
        self.y: C = None
        self.o: D = None
        self.q: B = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: A = None
        self.o: G = None
        self.t: A = None
        self.v: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: D = None
        self.z: I = None
        self.x: G = None
        self.p: A = None
        self.y: I = None
        self.txt = txt

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

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: A = None
        self.o: G = None
        self.t: A = None
        self.v: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: D = None
        self.z: I = None
        self.x: G = None
        self.p: A = None
        self.y: I = None
        self.txt = txt

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

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

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