class A:
    def __init__(self, txt: str):
        self.u: G = None
        self.s: G = None
        self.r: E = None
        self.y: A = None
        self.z: D = None
        self.x: E = None
        self.w: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.u: D = None
        self.t: E = None
        self.y: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.t: E = None
        self.txt = txt

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

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

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

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

g = A("g")
n = B("n")
m = C("m")
f = D("f")
l = E("l")
e = F("e")
k = G("k")
j = A("j")
i = E("i")

g.u = k
g.s = k
g.r = i
g.x = i
g.y = j
g.w = j
g.z = f
n.z = f
n.u = f
n.t = l
n.y = i
m.w = f
m.t = l
f.o = l
f.y = k
f.x = k
f.u = g
l.w = k
l.u = k
l.y = k
l.p = f
l.x = n
l.t = e
l.v = e
e.r = m
e.o = m
k.p = m
k.t = m
k.y = m
j.u = k
j.s = k
j.r = l
j.y = g
j.w = g
j.z = f
j.x = i
i.w = k
i.u = k
i.y = k
i.p = f
i.x = n
i.t = e
i.v = e
assert g.r.x.t.txt == "
class A:
    def __init__(self, txt: str):
        self.u: G = None
        self.s: G = None
        self.r: E = None
        self.y: A = None
        self.z: D = None
        self.x: E = None
        self.w: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.u: D = None
        self.t: E = None
        self.y: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.t: E = None
        self.txt = txt

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

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

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

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

g = A("g")
n = B("n")
m = C("m")
f = D("f")
l = E("l")
e = F("e")
k = G("k")
j = A("j")
i = E("i")

g.u = k
g.s = k
g.r = i
g.x = i
g.y = j
g.w = j
g.z = f
n.z = f
n.u = f
n.t = l
n.y = i
m.w = f
m.t = l
f.o = l
f.y = k
f.x = k
f.u = g
l.w = k
l.u = k
l.y = k
l.p = f
l.x = n
l.t = e
l.v = e
e.r = m
e.o = m
k.p = m
k.t = m
k.y = m
j.u = k
j.s = k
j.r = l
j.y = g
j.w = g
j.z = f
j.x = i
i.w = k
i.u = k
i.y = k
i.p = f
i.x = n
i.t = e
i.v = e
assert g.r.x.t.txt == "l"