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

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: G = None
        self.x: A = None
        self.y: D = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.z: E = None
        self.v: B = None
        self.y: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

j = A("j")
m = B("m")
d = C("d")
a = D("a")
h = E("h")
c = F("c")
i = G("i")
n = H("n")

j.w = c
j.t = i
j.p = n
j.v = a
m.s = c
m.x = n
d.v = h
d.o = i
d.x = j
d.y = a
a.r = d
h.x = d
h.y = d
h.r = n
h.u = n
h.w = a
h.z = i
h.t = m
h.v = c
c.z = h
c.v = m
c.y = n
i.r = m
i.t = a
i.z = n
i.u = n
i.v = d
i.w = j
n.w = a
assert i.z.w.r.o.t.txt == "
class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.t: G = None
        self.p: H = None
        self.v: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: G = None
        self.x: A = None
        self.y: D = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.z: E = None
        self.v: B = None
        self.y: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

j = A("j")
m = B("m")
d = C("d")
a = D("a")
h = E("h")
c = F("c")
i = G("i")
n = H("n")

j.w = c
j.t = i
j.p = n
j.v = a
m.s = c
m.x = n
d.v = h
d.o = i
d.x = j
d.y = a
a.r = d
h.x = d
h.y = d
h.r = n
h.u = n
h.w = a
h.z = i
h.t = m
h.v = c
c.z = h
c.v = m
c.y = n
i.r = m
i.t = a
i.z = n
i.u = n
i.v = d
i.w = j
n.w = a
assert i.z.w.r.o.t.txt == "a"