class A:
    def __init__(self, txt: str):
        self.r: B = None
        self.s: B = None
        self.u: J = None
        self.p: I = None
        self.o: D = None
        self.w: D = None
        self.v: J = None
        self.y: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: J = None
        self.q: G = None
        self.o: C = None
        self.x: E = None
        self.u: I = None
        self.z: H = None
        self.p: G = None
        self.t: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.p: J = None
        self.u: H = None
        self.y: E = None
        self.o: H = None
        self.r: I = None
        self.z: B = None
        self.x: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: H = None
        self.s: A = None
        self.t: I = None
        self.q: E = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: H = None
        self.x: J = None
        self.q: H = None
        self.w: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: J = None
        self.t: H = None
        self.v: I = None
        self.r: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: A = None
        self.u: G = None
        self.r: C = None
        self.v: J = None
        self.y: J = None
        self.x: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: B = None
        self.v: D = None
        self.p: E = None
        self.x: D = None
        self.q: G = None
        self.txt = txt

c = A("c")
i = B("i")
b = C("b")
h = D("h")
a = E("a")
l = F("l")
k = G("k")
f = H("f")
g = I("g")
n = J("n")

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

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.r: J = None
        self.q: G = None
        self.o: C = None
        self.x: E = None
        self.u: I = None
        self.z: H = None
        self.p: G = None
        self.t: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.p: J = None
        self.u: H = None
        self.y: E = None
        self.o: H = None
        self.r: I = None
        self.z: B = None
        self.x: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: H = None
        self.s: A = None
        self.t: I = None
        self.q: E = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: H = None
        self.x: J = None
        self.q: H = None
        self.w: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: J = None
        self.t: H = None
        self.v: I = None
        self.r: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: A = None
        self.u: G = None
        self.r: C = None
        self.v: J = None
        self.y: J = None
        self.x: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: D = None
        self.y: B = None
        self.v: D = None
        self.p: E = None
        self.x: D = None
        self.q: G = None
        self.txt = txt

c = A("c")
i = B("i")
b = C("b")
h = D("h")
a = E("a")
l = F("l")
k = G("k")
f = H("f")
g = I("g")
n = J("n")

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