class A:
    def __init__(self, txt: str):
        self.s: H = None
        self.v: H = None
        self.o: G = None
        self.q: F = None
        self.y: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.x: E = None
        self.t: F = None
        self.s: G = None
        self.w: J = None
        self.v: J = None
        self.q: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: F = None
        self.x: G = None
        self.y: G = None
        self.o: B = None
        self.s: B = None
        self.r: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: G = None
        self.w: I = None
        self.p: I = None
        self.r: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: H = None
        self.u: B = None
        self.s: B = None
        self.z: G = None
        self.r: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: G = None
        self.x: E = None
        self.t: F = None
        self.s: G = None
        self.w: J = None
        self.v: J = None
        self.q: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: F = None
        self.x: G = None
        self.y: G = None
        self.o: B = None
        self.s: B = None
        self.r: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: C = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: G = None
        self.w: I = None
        self.p: I = None
        self.r: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: H = None
        self.u: B = None
        self.s: B = None
        self.z: G = None
        self.r: F = None
        self.txt = txt

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

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