class A:
    def __init__(self, txt: str):
        self.u: G = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: J = None
        self.v: J = None
        self.y: A = None
        self.s: C = None
        self.z: F = None
        self.p: J = None
        self.o: A = None
        self.u: I = None
        self.t: D = None
        self.q: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: I = None
        self.p: F = None
        self.u: E = None
        self.w: E = None
        self.y: E = None
        self.t: G = None
        self.z: J = None
        self.r: F = None
        self.o: G = None
        self.q: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.w: H = None
        self.z: F = None
        self.o: B = None
        self.t: I = None
        self.x: A = None
        self.v: J = None
        self.s: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: I = None
        self.o: E = None
        self.x: H = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.t: F = None
        self.p: C = None
        self.q: F = None
        self.z: E = None
        self.o: A = None
        self.s: J = None
        self.w: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.s: B = None
        self.u: E = None
        self.y: G = None
        self.o: A = None
        self.r: J = None
        self.w: E = None
        self.q: B = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: J = None
        self.v: J = None
        self.y: A = None
        self.s: C = None
        self.z: F = None
        self.p: J = None
        self.o: A = None
        self.u: I = None
        self.t: D = None
        self.q: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: I = None
        self.p: F = None
        self.u: E = None
        self.w: E = None
        self.y: E = None
        self.t: G = None
        self.z: J = None
        self.r: F = None
        self.o: G = None
        self.q: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.w: H = None
        self.z: F = None
        self.o: B = None
        self.t: I = None
        self.x: A = None
        self.v: J = None
        self.s: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.q: I = None
        self.o: E = None
        self.x: H = None
        self.w: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.t: F = None
        self.p: C = None
        self.q: F = None
        self.z: E = None
        self.o: A = None
        self.s: J = None
        self.w: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.s: B = None
        self.u: E = None
        self.y: G = None
        self.o: A = None
        self.r: J = None
        self.w: E = None
        self.q: B = None
        self.txt = txt

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

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

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