class A:
    def __init__(self, txt: str):
        self.w: H = None
        self.p: I = None
        self.z: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.w: D = None
        self.z: C = None
        self.y: H = None
        self.u: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.r: B = None
        self.z: G = None
        self.t: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.p: I = None
        self.o: I = None
        self.x: A = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: C = None
        self.s: H = None
        self.q: D = None
        self.u: F = None
        self.p: D = None
        self.o: F = None
        self.x: F = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: B = None
        self.x: B = None
        self.v: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: A = None
        self.s: B = None
        self.z: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.w: D = None
        self.z: C = None
        self.y: H = None
        self.u: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.r: B = None
        self.z: G = None
        self.t: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.p: I = None
        self.o: I = None
        self.x: A = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: C = None
        self.s: H = None
        self.q: D = None
        self.u: F = None
        self.p: D = None
        self.o: F = None
        self.x: F = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.w: B = None
        self.x: B = None
        self.v: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: A = None
        self.s: B = None
        self.z: D = None
        self.txt = txt

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

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