class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: G = None
        self.o: G = None
        self.z: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: E = None
        self.p: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.r: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.r: A = None
        self.y: D = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: C = None
        self.v: B = None
        self.w: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: E = None
        self.p: B = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.r: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.r: A = None
        self.y: D = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: C = None
        self.v: B = None
        self.w: G = None
        self.txt = txt

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

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