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

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

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

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.r: A = None
        self.u: G = None
        self.v: F = None
        self.w: E = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: A = None
        self.q: F = None
        self.x: F = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.r: A = None
        self.u: G = None
        self.v: F = None
        self.w: E = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: A = None
        self.q: F = None
        self.x: F = None
        self.txt = txt

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

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

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

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