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

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

class C:
    def __init__(self, txt: str):
        self.y: H = None
        self.t: G = None
        self.p: E = None
        self.q: H = None
        self.s: D = None
        self.v: H = None
        self.r: D = None
        self.o: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.t: F = None
        self.p: H = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.r: D = None
        self.x: D = None
        self.q: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: H = None
        self.y: C = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: C = None
        self.p: A = None
        self.o: E = None
        self.w: C = None
        self.txt = txt

e = A("e")
g = B("g")
h = C("h")
a = D("a")
c = E("c")
i = F("i")
b = G("b")
l = H("l")

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

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

class C:
    def __init__(self, txt: str):
        self.y: H = None
        self.t: G = None
        self.p: E = None
        self.q: H = None
        self.s: D = None
        self.v: H = None
        self.r: D = None
        self.o: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.t: F = None
        self.p: H = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.r: D = None
        self.x: D = None
        self.q: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: H = None
        self.y: C = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: C = None
        self.p: A = None
        self.o: E = None
        self.w: C = None
        self.txt = txt

e = A("e")
g = B("g")
h = C("h")
a = D("a")
c = E("c")
i = F("i")
b = G("b")
l = H("l")

e.u = i
e.t = c
g.z = b
g.x = b
g.s = h
g.y = e
g.p = i
g.o = c
h.y = l
h.q = l
h.v = l
h.t = b
h.o = b
h.p = c
h.s = a
h.r = a
a.r = g
a.t = i
a.p = l
a.q = h
c.t = b
c.q = b
c.r = a
c.x = a
i.t = b
i.v = b
i.y = l
b.x = e
b.s = l
b.y = h
b.z = i
l.y = h
l.w = h
l.p = e
l.o = c
assert b.s.p.u.y.txt == "l"