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

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.r: G = None
        self.p: A = None
        self.z: B = None
        self.u: I = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.r: G = None
        self.p: A = None
        self.z: B = None
        self.u: I = None
        self.txt = txt

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

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

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

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

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

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