class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.v: B = None
        self.s: D = None
        self.x: D = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: D = None
        self.x: G = None
        self.u: A = None
        self.q: C = None
        self.y: B = None
        self.txt = txt

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

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

m = A("m")
a = B("a")
i = C("i")
k = D("k")
l = E("l")
c = F("c")
g = G("g")
b = G("b")
h = B("h")

m.w = c
m.v = a
m.s = k
m.x = k
a.u = k
a.v = c
a.y = i
a.r = g
a.o = b
a.z = m
a.t = h
i.u = k
k.s = l
k.x = b
l.z = k
l.x = b
l.u = m
l.q = i
l.y = h
c.q = b
g.x = m
g.r = b
g.v = b
g.t = c
b.x = m
b.r = g
b.v = g
b.t = c
h.u = k
h.v = c
h.y = i
h.r = b
h.o = g
h.z = m
h.t = a
assert a.z.v.u.txt == "
class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.v: B = None
        self.s: D = None
        self.x: D = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: D = None
        self.x: G = None
        self.u: A = None
        self.q: C = None
        self.y: B = None
        self.txt = txt

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

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

m = A("m")
a = B("a")
i = C("i")
k = D("k")
l = E("l")
c = F("c")
g = G("g")
b = G("b")
h = B("h")

m.w = c
m.v = a
m.s = k
m.x = k
a.u = k
a.v = c
a.y = i
a.r = g
a.o = b
a.z = m
a.t = h
i.u = k
k.s = l
k.x = b
l.z = k
l.x = b
l.u = m
l.q = i
l.y = h
c.q = b
g.x = m
g.r = b
g.v = b
g.t = c
b.x = m
b.r = g
b.v = g
b.t = c
h.u = k
h.v = c
h.y = i
h.r = b
h.o = g
h.z = m
h.t = a
assert a.z.v.u.txt == "k"