class A:
    def __init__(self, txt: str):
        self.y: D = None
        self.p: F = None
        self.r: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: G = None
        self.z: F = None
        self.s: G = None
        self.t: D = None
        self.v: G = None
        self.q: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: I = None
        self.p: E = None
        self.o: A = None
        self.x: A = None
        self.y: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: I = None
        self.r: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: H = None
        self.u: B = None
        self.y: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: D = None
        self.p: C = None
        self.o: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.w: G = None
        self.z: F = None
        self.s: G = None
        self.t: D = None
        self.v: G = None
        self.q: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: I = None
        self.p: E = None
        self.o: A = None
        self.x: A = None
        self.y: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: I = None
        self.r: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: H = None
        self.u: B = None
        self.y: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: D = None
        self.p: C = None
        self.o: F = None
        self.txt = txt

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

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

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