class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: C = None
        self.u: F = None
        self.s: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.y: E = None
        self.s: B = None
        self.p: F = None
        self.x: G = None
        self.z: C = None
        self.t: B = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.p: G = None
        self.v: B = None
        self.q: A = None
        self.txt = txt

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

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

f = A("f")
a = B("a")
l = C("l")
k = D("k")
d = E("d")
c = F("c")
j = G("j")
h = B("h")
i = F("i")

f.w = i
f.u = i
f.q = l
f.s = k
a.q = d
a.y = d
a.s = h
a.t = h
a.p = i
a.x = j
a.z = l
l.y = j
l.x = a
l.q = a
l.z = d
l.u = f
l.v = f
k.x = c
d.z = c
d.p = j
d.v = h
d.q = f
c.z = d
c.t = d
c.v = l
c.s = j
c.w = j
c.u = j
c.x = h
j.t = i
j.y = h
h.q = d
h.y = d
h.s = a
h.t = a
h.p = c
h.x = j
h.z = l
i.z = d
i.t = d
i.v = l
i.s = j
i.w = j
i.u = j
i.x = a
assert h.y.v.x.t.txt == "
class A:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: C = None
        self.u: F = None
        self.s: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.y: E = None
        self.s: B = None
        self.p: F = None
        self.x: G = None
        self.z: C = None
        self.t: B = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.p: G = None
        self.v: B = None
        self.q: A = None
        self.txt = txt

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

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

f = A("f")
a = B("a")
l = C("l")
k = D("k")
d = E("d")
c = F("c")
j = G("j")
h = B("h")
i = F("i")

f.w = i
f.u = i
f.q = l
f.s = k
a.q = d
a.y = d
a.s = h
a.t = h
a.p = i
a.x = j
a.z = l
l.y = j
l.x = a
l.q = a
l.z = d
l.u = f
l.v = f
k.x = c
d.z = c
d.p = j
d.v = h
d.q = f
c.z = d
c.t = d
c.v = l
c.s = j
c.w = j
c.u = j
c.x = h
j.t = i
j.y = h
h.q = d
h.y = d
h.s = a
h.t = a
h.p = c
h.x = j
h.z = l
i.z = d
i.t = d
i.v = l
i.s = j
i.w = j
i.u = j
i.x = a
assert h.y.v.x.t.txt == "i"