class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.u: H = None
        self.w: H = None
        self.r: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.o: I = None
        self.w: H = None
        self.y: A = None
        self.u: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: C = None
        self.x: H = None
        self.w: B = None
        self.s: E = None
        self.p: C = None
        self.q: E = None
        self.v: A = None
        self.y: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: C = None
        self.z: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: J = None
        self.r: G = None
        self.o: C = None
        self.p: E = None
        self.t: G = None
        self.v: E = None
        self.u: D = None
        self.s: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.o: I = None
        self.w: H = None
        self.y: A = None
        self.u: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: C = None
        self.x: H = None
        self.w: B = None
        self.s: E = None
        self.p: C = None
        self.q: E = None
        self.v: A = None
        self.y: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: C = None
        self.z: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: J = None
        self.r: G = None
        self.o: C = None
        self.p: E = None
        self.t: G = None
        self.v: E = None
        self.u: D = None
        self.s: F = None
        self.txt = txt

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

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

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