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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.z: C = None
        self.u: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: I = None
        self.y: E = None
        self.w: G = None
        self.z: F = None
        self.o: E = None
        self.p: I = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.q: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: I = None
        self.s: F = None
        self.u: G = None
        self.z: D = None
        self.v: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.q: I = None
        self.v: B = None
        self.u: F = None
        self.x: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.x: B = None
        self.z: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.z: C = None
        self.u: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: I = None
        self.y: E = None
        self.w: G = None
        self.z: F = None
        self.o: E = None
        self.p: I = None
        self.s: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.q: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: I = None
        self.s: F = None
        self.u: G = None
        self.z: D = None
        self.v: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: A = None
        self.q: I = None
        self.v: B = None
        self.u: F = None
        self.x: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.x: B = None
        self.z: C = None
        self.txt = txt

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

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