class A:
    def __init__(self, txt: str):
        self.u: H = None
        self.y: C = None
        self.o: G = None
        self.t: D = None
        self.q: C = None
        self.p: I = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: H = None
        self.w: E = None
        self.s: I = None
        self.y: B = None
        self.v: A = None
        self.q: A = None
        self.r: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.p: H = None
        self.q: E = None
        self.x: A = None
        self.w: I = None
        self.u: E = None
        self.s: I = None
        self.y: B = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.w: D = None
        self.t: E = None
        self.y: D = None
        self.u: G = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: H = None
        self.w: E = None
        self.s: I = None
        self.y: B = None
        self.v: A = None
        self.q: A = None
        self.r: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.p: H = None
        self.q: E = None
        self.x: A = None
        self.w: I = None
        self.u: E = None
        self.s: I = None
        self.y: B = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.w: D = None
        self.t: E = None
        self.y: D = None
        self.u: G = None
        self.txt = txt

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

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