class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.q: F = None
        self.p: D = None
        self.r: C = None
        self.s: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.p: H = None
        self.t: E = None
        self.v: C = None
        self.y: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.y: D = None
        self.x: E = None
        self.o: E = None
        self.w: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: G = None
        self.w: F = None
        self.v: A = None
        self.z: G = None
        self.p: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.p: H = None
        self.t: E = None
        self.v: C = None
        self.y: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.y: D = None
        self.x: E = None
        self.o: E = None
        self.w: A = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: G = None
        self.w: F = None
        self.v: A = None
        self.z: G = None
        self.p: G = None
        self.txt = txt

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

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