class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: B = None
        self.x: E = None
        self.w: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.v: F = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.w: D = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: F = None
        self.x: C = None
        self.txt = txt

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

i = A("i")
j = B("j")
g = C("g")
h = D("h")
d = E("d")
k = F("k")
n = G("n")
b = C("b")
a = F("a")

i.t = j
i.z = j
i.x = d
i.w = k
j.y = i
g.y = j
g.x = a
h.s = k
h.v = a
h.t = d
d.u = n
d.y = n
d.w = h
k.w = j
k.y = a
k.x = g
n.y = g
n.x = d
b.y = j
b.x = k
a.w = j
a.y = k
a.x = b
assert i.x.w.s.y.y.w.y.x.txt == "
class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.z: B = None
        self.x: E = None
        self.w: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: F = None
        self.v: F = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.w: D = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: F = None
        self.x: C = None
        self.txt = txt

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

i = A("i")
j = B("j")
g = C("g")
h = D("h")
d = E("d")
k = F("k")
n = G("n")
b = C("b")
a = F("a")

i.t = j
i.z = j
i.x = d
i.w = k
j.y = i
g.y = j
g.x = a
h.s = k
h.v = a
h.t = d
d.u = n
d.y = n
d.w = h
k.w = j
k.y = a
k.x = g
n.y = g
n.x = d
b.y = j
b.x = k
a.w = j
a.y = k
a.x = b
assert i.x.w.s.y.y.w.y.x.txt == "d"