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

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

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

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

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