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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.x: G = None
        self.r: A = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.y: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: H = None
        self.s: G = None
        self.y: A = None
        self.x: G = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: B = None
        self.u: G = None
        self.y: G = None
        self.q: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.x: G = None
        self.r: A = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.y: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: H = None
        self.s: G = None
        self.y: A = None
        self.x: G = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: B = None
        self.u: G = None
        self.y: G = None
        self.q: H = None
        self.txt = txt

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

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