class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.z: D = None
        self.v: G = None
        self.t: F = None
        self.s: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: G = None
        self.u: D = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: D = None
        self.u: F = None
        self.x: B = None
        self.p: B = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: G = None
        self.u: D = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: D = None
        self.u: F = None
        self.x: B = None
        self.p: B = None
        self.txt = txt

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

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

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

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