class A:
    def __init__(self, txt: str):
        self.w: J = None
        self.q: D = None
        self.y: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.v: H = None
        self.p: B = None
        self.t: H = None
        self.r: H = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.x: F = None
        self.v: I = None
        self.y: J = None
        self.r: B = None
        self.s: D = None
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: F = None
        self.w: H = None
        self.txt = txt

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

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

e.w = i
e.q = c
e.y = j
m.x = d
m.y = i
m.r = k
m.s = k
m.u = e
m.v = e
m.o = j
m.t = j
b.u = j
b.v = d
b.t = d
b.r = d
b.p = m
c.o = a
k.o = e
k.s = b
k.y = b
k.q = j
k.x = j
k.r = a
k.v = c
j.t = a
l.p = m
l.r = m
l.x = j
l.w = j
l.v = a
l.y = i
l.s = c
d.s = l
a.o = d
a.w = d
a.s = j
i.t = d
i.s = e
i.v = a
i.x = a
i.y = a
i.w = c
i.o = k
assert d.s.v.o.s.s.txt == "
class A:
    def __init__(self, txt: str):
        self.w: J = None
        self.q: D = None
        self.y: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: F = None
        self.v: H = None
        self.p: B = None
        self.t: H = None
        self.r: H = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.x: F = None
        self.v: I = None
        self.y: J = None
        self.r: B = None
        self.s: D = None
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: F = None
        self.w: H = None
        self.txt = txt

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

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

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