class A:
    def __init__(self, txt: str):
        self.v: I = None
        self.x: H = None
        self.r: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: B = None
        self.z: I = None
        self.t: F = None
        self.y: H = None
        self.r: A = None
        self.p: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: H = None
        self.y: H = None
        self.u: I = None
        self.w: H = None
        self.z: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.o: D = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: G = None
        self.t: A = None
        self.z: H = None
        self.q: E = None
        self.x: F = None
        self.r: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: B = None
        self.z: I = None
        self.t: F = None
        self.y: H = None
        self.r: A = None
        self.p: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: H = None
        self.y: H = None
        self.u: I = None
        self.w: H = None
        self.z: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.o: D = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: G = None
        self.t: A = None
        self.z: H = None
        self.q: E = None
        self.x: F = None
        self.r: D = None
        self.txt = txt

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

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