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

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.w: H = None
        self.z: I = None
        self.p: E = None
        self.q: D = None
        self.r: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.r: D = None
        self.v: G = None
        self.w: A = None
        self.z: E = None
        self.t: A = None
        self.s: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.x: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: D = None
        self.txt = txt

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

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

c = A("c")
k = B("k")
i = C("i")
b = D("b")
f = E("f")
l = F("l")
m = G("m")
a = H("a")
e = I("e")
d = A("d")

c.z = f
c.p = e
k.v = l
k.w = a
k.z = e
k.p = f
k.q = b
k.r = i
i.u = m
i.v = m
i.s = m
i.r = b
i.w = d
i.z = f
i.t = c
b.v = k
f.q = c
l.x = i
m.z = b
a.s = i
a.z = i
a.v = l
a.u = m
e.s = m
e.u = f
e.o = l
e.t = l
e.r = b
e.q = c
e.z = k
e.x = i
d.z = f
d.p = e
assert f.q.z.q.p.o.x.txt == "
class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.p: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.w: H = None
        self.z: I = None
        self.p: E = None
        self.q: D = None
        self.r: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.r: D = None
        self.v: G = None
        self.w: A = None
        self.z: E = None
        self.t: A = None
        self.s: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.x: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: D = None
        self.txt = txt

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

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

c = A("c")
k = B("k")
i = C("i")
b = D("b")
f = E("f")
l = F("l")
m = G("m")
a = H("a")
e = I("e")
d = A("d")

c.z = f
c.p = e
k.v = l
k.w = a
k.z = e
k.p = f
k.q = b
k.r = i
i.u = m
i.v = m
i.s = m
i.r = b
i.w = d
i.z = f
i.t = c
b.v = k
f.q = c
l.x = i
m.z = b
a.s = i
a.z = i
a.v = l
a.u = m
e.s = m
e.u = f
e.o = l
e.t = l
e.r = b
e.q = c
e.z = k
e.x = i
d.z = f
d.p = e
assert f.q.z.q.p.o.x.txt == "i"