class A:
    def __init__(self, txt: str):
        self.p: F = None
        self.z: G = None
        self.r: F = None
        self.u: I = None
        self.v: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.v: A = None
        self.z: A = None
        self.w: H = None
        self.u: E = None
        self.q: B = None
        self.r: B = None
        self.p: E = None
        self.o: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.x: B = None
        self.v: A = None
        self.p: C = None
        self.y: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: D = None
        self.o: D = None
        self.u: E = None
        self.z: I = None
        self.x: A = None
        self.t: B = None
        self.y: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: F = None
        self.q: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: G = None
        self.s: H = None
        self.t: E = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.v: A = None
        self.z: A = None
        self.w: H = None
        self.u: E = None
        self.q: B = None
        self.r: B = None
        self.p: E = None
        self.o: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.x: B = None
        self.v: A = None
        self.p: C = None
        self.y: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: D = None
        self.o: D = None
        self.u: E = None
        self.z: I = None
        self.x: A = None
        self.t: B = None
        self.y: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: F = None
        self.q: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: G = None
        self.s: H = None
        self.t: E = None
        self.txt = txt

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

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