class A:
    def __init__(self, txt: str):
        self.s: I = None
        self.u: E = None
        self.w: H = None
        self.q: I = None
        self.p: E = None
        self.v: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: F = None
        self.y: G = None
        self.p: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: G = None
        self.o: A = None
        self.q: B = None
        self.p: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: F = None
        self.y: G = None
        self.p: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: G = None
        self.o: A = None
        self.q: B = None
        self.p: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: G = None
        self.txt = txt

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

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

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