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

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.o: A = None
        self.t: C = None
        self.p: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.y: C = None
        self.u: I = None
        self.x: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.x: I = None
        self.z: F = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.z: H = None
        self.x: D = None
        self.v: B = None
        self.s: C = None
        self.txt = txt

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

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

d.z = a
d.t = a
d.w = c
d.o = f
d.x = h
d.s = e
j.s = k
j.o = d
j.t = f
j.p = m
f.z = a
a.v = l
a.x = l
a.y = f
a.u = k
c.v = j
c.x = k
c.z = e
e.t = h
e.q = f
e.v = c
e.s = c
e.y = k
e.w = l
e.x = j
m.w = h
m.q = c
l.y = j
l.v = j
l.z = h
l.x = a
l.s = f
k.t = e
h.y = j
h.v = j
h.z = l
h.x = a
h.s = f
assert l.z.z.v.o.t.u.t.t.y.txt == "
class A:
    def __init__(self, txt: str):
        self.z: D = None
        self.w: E = None
        self.o: C = None
        self.x: H = None
        self.t: D = None
        self.s: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: I = None
        self.o: A = None
        self.t: C = None
        self.p: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.y: C = None
        self.u: I = None
        self.x: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.x: I = None
        self.z: F = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.z: H = None
        self.x: D = None
        self.v: B = None
        self.s: C = None
        self.txt = txt

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

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

d.z = a
d.t = a
d.w = c
d.o = f
d.x = h
d.s = e
j.s = k
j.o = d
j.t = f
j.p = m
f.z = a
a.v = l
a.x = l
a.y = f
a.u = k
c.v = j
c.x = k
c.z = e
e.t = h
e.q = f
e.v = c
e.s = c
e.y = k
e.w = l
e.x = j
m.w = h
m.q = c
l.y = j
l.v = j
l.z = h
l.x = a
l.s = f
k.t = e
h.y = j
h.v = j
h.z = l
h.x = a
h.s = f
assert l.z.z.v.o.t.u.t.t.y.txt == "j"