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

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

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.v: D = None
        self.x: I = None
        self.s: D = None
        self.r: G = None
        self.o: B = None
        self.u: E = None
        self.p: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.x: I = None
        self.w: H = None
        self.u: D = None
        self.s: C = None
        self.o: F = None
        self.z: C = None
        self.y: B = None
        self.txt = txt

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

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

h = A("h")
l = B("l")
c = C("c")
i = D("i")
d = E("d")
k = F("k")
e = G("e")
g = H("g")
f = I("f")
b = D("b")

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

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

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.t: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.v: D = None
        self.x: I = None
        self.s: D = None
        self.r: G = None
        self.o: B = None
        self.u: E = None
        self.p: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.x: I = None
        self.w: H = None
        self.u: D = None
        self.s: C = None
        self.o: F = None
        self.z: C = None
        self.y: B = None
        self.txt = txt

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

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

h = A("h")
l = B("l")
c = C("c")
i = D("i")
d = E("d")
k = F("k")
e = G("e")
g = H("g")
f = I("f")
b = D("b")

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