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

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: D = None
        self.r: D = None
        self.v: C = None
        self.q: A = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.o: H = None
        self.s: A = None
        self.q: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: F = None
        self.t: D = None
        self.r: D = None
        self.o: F = None
        self.w: I = None
        self.v: F = None
        self.u: I = None
        self.z: F = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: D = None
        self.r: D = None
        self.v: C = None
        self.q: A = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: G = None
        self.o: H = None
        self.s: A = None
        self.q: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: F = None
        self.t: D = None
        self.r: D = None
        self.o: F = None
        self.w: I = None
        self.v: F = None
        self.u: I = None
        self.z: F = None
        self.txt = txt

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

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

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

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