class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.z: I = None
        self.p: B = None
        self.w: F = None
        self.q: D = None
        self.v: E = None
        self.x: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: H = None
        self.y: F = None
        self.w: F = None
        self.p: E = None
        self.z: F = None
        self.u: B = None
        self.r: B = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.r: I = None
        self.p: H = None
        self.u: C = None
        self.x: A = None
        self.w: E = None
        self.y: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: G = None
        self.p: I = None
        self.t: G = None
        self.s: G = None
        self.x: D = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: H = None
        self.y: F = None
        self.w: F = None
        self.p: E = None
        self.z: F = None
        self.u: B = None
        self.r: B = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: C = None
        self.r: I = None
        self.p: H = None
        self.u: C = None
        self.x: A = None
        self.w: E = None
        self.y: F = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: G = None
        self.p: I = None
        self.t: G = None
        self.s: G = None
        self.x: D = None
        self.txt = txt

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

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

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