class A:
    def __init__(self, txt: str):
        self.z: I = None
        self.s: F = None
        self.y: E = None
        self.q: D = None
        self.x: I = None
        self.p: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: F = None
        self.v: H = None
        self.y: A = None
        self.t: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: F = None
        self.v: H = None
        self.y: A = None
        self.t: H = None
        self.txt = txt

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

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