class A:
    def __init__(self, txt: str):
        self.u: B = None
        self.v: E = None
        self.p: C = None
        self.x: C = None
        self.y: F = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: D = None
        self.y: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.s: B = None
        self.u: B = None
        self.w: G = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: G = None
        self.p: G = None
        self.q: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: A = None
        self.s: H = None
        self.t: H = None
        self.q: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.u: F = None
        self.p: I = None
        self.v: E = None
        self.r: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.u: B = None
        self.y: B = None
        self.v: F = None
        self.o: C = None
        self.t: G = None
        self.w: D = None
        self.z: H = None
        self.x: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: D = None
        self.y: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.s: B = None
        self.u: B = None
        self.w: G = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: G = None
        self.p: G = None
        self.q: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: A = None
        self.s: H = None
        self.t: H = None
        self.q: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: F = None
        self.u: F = None
        self.p: I = None
        self.v: E = None
        self.r: D = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.u: B = None
        self.y: B = None
        self.v: F = None
        self.o: C = None
        self.t: G = None
        self.w: D = None
        self.z: H = None
        self.x: F = None
        self.txt = txt

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

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