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

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.x: D = None
        self.p: I = None
        self.q: I = None
        self.z: A = None
        self.r: I = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: F = None
        self.r: A = None
        self.x: A = None
        self.t: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.x: D = None
        self.p: I = None
        self.q: I = None
        self.z: A = None
        self.r: I = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: F = None
        self.r: A = None
        self.x: A = None
        self.t: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.txt = txt

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

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