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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: A = None
        self.o: E = None
        self.w: A = None
        self.t: A = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: A = None
        self.o: E = None
        self.w: A = None
        self.t: A = None
        self.txt = txt

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

e.w = i
e.v = b
e.s = g
e.u = m
e.x = c
b.z = g
b.p = f
m.y = l
f.x = b
f.t = l
f.z = l
f.o = m
f.s = m
f.q = g
f.y = c
g.w = e
g.u = b
g.z = m
g.p = l
g.v = l
g.q = l
g.t = i
k.s = b
l.u = i
l.w = i
l.o = g
l.t = e
i.w = c
i.x = c
i.v = b
i.s = g
i.u = m
c.w = e
c.x = e
c.v = b
c.s = g
c.u = m
assert l.u.u.y.txt == "l"