class A:
    def __init__(self, txt: str):
        self.y: F = None
        self.o: E = None
        self.v: A = None
        self.z: E = None
        self.u: F = None
        self.w: F = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: G = None
        self.s: E = None
        self.q: B = None
        self.v: C = None
        self.w: B = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.q: A = None
        self.w: B = None
        self.z: A = None
        self.p: A = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: G = None
        self.s: E = None
        self.q: B = None
        self.v: C = None
        self.w: B = None
        self.r: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: A = None
        self.q: A = None
        self.w: B = None
        self.z: A = None
        self.p: A = None
        self.txt = txt

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

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