class A:
    def __init__(self, txt: str):
        self.x: E = None
        self.z: E = None
        self.v: D = None
        self.u: C = None
        self.q: G = None
        self.y: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.z: H = None
        self.q: F = None
        self.p: E = None
        self.x: H = None
        self.r: I = None
        self.u: E = None
        self.v: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: C = None
        self.p: E = None
        self.u: H = None
        self.t: F = None
        self.v: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.s: G = None
        self.w: F = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.z: B = None
        self.t: C = None
        self.v: I = None
        self.x: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.z: H = None
        self.q: F = None
        self.p: E = None
        self.x: H = None
        self.r: I = None
        self.u: E = None
        self.v: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: C = None
        self.p: E = None
        self.u: H = None
        self.t: F = None
        self.v: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.s: G = None
        self.w: F = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: F = None
        self.z: B = None
        self.t: C = None
        self.v: I = None
        self.x: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: A = None
        self.txt = txt

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

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