class A:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.z: C = None
        self.s: C = None
        self.q: F = None
        self.v: H = None
        self.t: D = None
        self.o: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: D = None
        self.t: D = None
        self.x: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.w: F = None
        self.p: D = None
        self.q: D = None
        self.txt = txt

h = A("h")
g = B("g")
j = C("j")
e = D("e")
i = E("i")
a = F("a")
n = G("n")
m = H("m")
k = I("k")
c = B("c")

h.z = a
g.v = a
j.y = m
e.z = c
e.t = a
e.s = k
e.w = m
i.y = k
i.o = k
i.z = j
i.s = j
i.q = a
i.v = m
i.t = e
a.r = j
a.v = e
a.t = e
a.x = g
n.z = m
n.r = h
n.s = k
m.r = j
m.t = i
m.z = k
k.s = c
k.w = a
k.p = e
k.q = e
c.v = a
assert c.v.r.y.t.y.txt == "
class A:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.z: C = None
        self.s: C = None
        self.q: F = None
        self.v: H = None
        self.t: D = None
        self.o: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: D = None
        self.t: D = None
        self.x: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.s: B = None
        self.w: F = None
        self.p: D = None
        self.q: D = None
        self.txt = txt

h = A("h")
g = B("g")
j = C("j")
e = D("e")
i = E("i")
a = F("a")
n = G("n")
m = H("m")
k = I("k")
c = B("c")

h.z = a
g.v = a
j.y = m
e.z = c
e.t = a
e.s = k
e.w = m
i.y = k
i.o = k
i.z = j
i.s = j
i.q = a
i.v = m
i.t = e
a.r = j
a.v = e
a.t = e
a.x = g
n.z = m
n.r = h
n.s = k
m.r = j
m.t = i
m.z = k
k.s = c
k.w = a
k.p = e
k.q = e
c.v = a
assert c.v.r.y.t.y.txt == "k"