class A:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: G = None
        self.w: H = None
        self.o: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: E = None
        self.r: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.q: G = None
        self.o: I = None
        self.v: G = None
        self.s: A = None
        self.p: E = None
        self.w: I = None
        self.r: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: F = None
        self.p: F = None
        self.q: I = None
        self.o: F = None
        self.s: G = None
        self.w: F = None
        self.t: H = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: E = None
        self.r: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.q: G = None
        self.o: I = None
        self.v: G = None
        self.s: A = None
        self.p: E = None
        self.w: I = None
        self.r: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: F = None
        self.p: F = None
        self.q: I = None
        self.o: F = None
        self.s: G = None
        self.w: F = None
        self.t: H = None
        self.txt = txt

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

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

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

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

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

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