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

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.x: E = None
        self.w: I = None
        self.o: I = None
        self.z: J = None
        self.u: J = None
        self.r: D = None
        self.s: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.y: C = None
        self.o: H = None
        self.r: G = None
        self.s: B = None
        self.x: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.z: C = None
        self.x: D = None
        self.s: A = None
        self.v: A = None
        self.w: H = None
        self.y: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: J = None
        self.x: E = None
        self.w: I = None
        self.o: I = None
        self.z: J = None
        self.u: J = None
        self.r: D = None
        self.s: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: G = None
        self.v: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.y: C = None
        self.o: H = None
        self.r: G = None
        self.s: B = None
        self.x: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.z: C = None
        self.x: D = None
        self.s: A = None
        self.v: A = None
        self.w: H = None
        self.y: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

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