class A:
    def __init__(self, txt: str):
        self.x: F = None
        self.s: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: A = None
        self.t: D = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: A = None
        self.t: D = None
        self.z: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

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

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

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