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

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

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

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

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

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

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

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

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

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

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

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

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