class A:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.r: I = None
        self.z: G = None
        self.y: I = None
        self.v: E = None
        self.o: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: I = None
        self.s: D = None
        self.r: H = None
        self.x: D = None
        self.p: C = None
        self.z: E = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: F = None
        self.o: B = None
        self.u: B = None
        self.t: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: E = None
        self.s: G = None
        self.t: A = None
        self.p: E = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.r: I = None
        self.z: G = None
        self.y: I = None
        self.v: E = None
        self.o: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: I = None
        self.s: D = None
        self.r: H = None
        self.x: D = None
        self.p: C = None
        self.z: E = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: F = None
        self.o: B = None
        self.u: B = None
        self.t: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: E = None
        self.s: G = None
        self.t: A = None
        self.p: E = None
        self.txt = txt

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

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

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