class A:
    def __init__(self, txt: str):
        self.z: C = None
        self.r: F = None
        self.u: D = None
        self.p: D = None
        self.t: C = None
        self.w: B = None
        self.y: B = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: D = None
        self.z: A = None
        self.txt = txt

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

k = A("k")
n = B("n")
e = C("e")
l = D("l")
j = E("j")
a = F("a")
h = G("h")
c = F("c")
d = B("d")
i = G("i")

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: D = None
        self.z: A = None
        self.txt = txt

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

k = A("k")
n = B("n")
e = C("e")
l = D("l")
j = E("j")
a = F("a")
h = G("h")
c = F("c")
d = B("d")
i = G("i")

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