class A:
    def __init__(self, txt: str):
        self.u: H = None
        self.x: G = None
        self.r: G = None
        self.s: C = None
        self.p: B = None
        self.t: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: I = None
        self.y: I = None
        self.r: B = None
        self.s: B = None
        self.t: D = None
        self.z: I = None
        self.q: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: E = None
        self.z: F = None
        self.t: F = None
        self.u: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: B = None
        self.v: B = None
        self.t: H = None
        self.u: A = None
        self.s: H = None
        self.w: A = None
        self.r: C = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: I = None
        self.y: I = None
        self.r: B = None
        self.s: B = None
        self.t: D = None
        self.z: I = None
        self.q: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: E = None
        self.z: F = None
        self.t: F = None
        self.u: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: B = None
        self.v: B = None
        self.t: H = None
        self.u: A = None
        self.s: H = None
        self.w: A = None
        self.r: C = None
        self.txt = txt

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

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