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

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.r: C = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

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

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

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

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

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

j = A("j")
b = B("b")
m = C("m")
c = D("c")
k = E("k")
g = F("g")
f = G("f")
a = H("a")
i = D("i")

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

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.r: C = None
        self.y: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

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

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

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

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

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

j = A("j")
b = B("b")
m = C("m")
c = D("c")
k = E("k")
g = F("g")
f = G("f")
a = H("a")
i = D("i")

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