class A:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: G = None
        self.o: F = None
        self.r: B = None
        self.u: A = None
        self.p: A = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: C = None
        self.p: C = None
        self.s: A = None
        self.u: B = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.p: E = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: A = None
        self.o: C = None
        self.p: C = None
        self.s: A = None
        self.u: B = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: F = None
        self.p: E = None
        self.txt = txt

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

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

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

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

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