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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: H = None
        self.w: C = None
        self.r: F = None
        self.o: D = None
        self.y: I = None
        self.p: H = None
        self.q: G = None
        self.s: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: H = None
        self.s: E = None
        self.y: B = None
        self.o: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.w: B = None
        self.q: B = None
        self.s: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.v: D = None
        self.u: A = None
        self.w: B = None
        self.z: B = None
        self.t: D = None
        self.q: B = None
        self.x: G = None
        self.p: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: I = None
        self.u: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: C = None
        self.p: G = None
        self.u: A = None
        self.v: B = None
        self.t: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: D = None
        self.x: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: H = None
        self.w: C = None
        self.r: F = None
        self.o: D = None
        self.y: I = None
        self.p: H = None
        self.q: G = None
        self.s: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.w: H = None
        self.s: E = None
        self.y: B = None
        self.o: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.w: B = None
        self.q: B = None
        self.s: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.v: D = None
        self.u: A = None
        self.w: B = None
        self.z: B = None
        self.t: D = None
        self.q: B = None
        self.x: G = None
        self.p: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: I = None
        self.u: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: C = None
        self.p: G = None
        self.u: A = None
        self.v: B = None
        self.t: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: D = None
        self.x: B = None
        self.txt = txt

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

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