class A:
    def __init__(self, txt: str):
        self.u: G = None
        self.p: G = None
        self.x: G = None
        self.w: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: C = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: E = None
        self.o: F = None
        self.p: E = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: C = None
        self.txt = txt

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: E = None
        self.o: F = None
        self.p: E = None
        self.txt = txt

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

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

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

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