class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.p: I = None
        self.q: E = None
        self.w: I = None
        self.v: I = None
        self.s: J = None
        self.r: C = None
        self.u: I = None
        self.y: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.w: E = None
        self.r: J = None
        self.p: I = None
        self.t: B = None
        self.y: H = None
        self.x: F = None
        self.z: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.w: B = None
        self.x: C = None
        self.y: J = None
        self.s: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.v: B = None
        self.o: G = None
        self.u: G = None
        self.p: A = None
        self.t: I = None
        self.y: A = None
        self.q: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: I = None
        self.p: G = None
        self.w: D = None
        self.x: G = None
        self.v: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: C = None
        self.p: A = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: A = None
        self.y: I = None
        self.q: F = None
        self.p: D = None
        self.r: E = None
        self.u: E = None
        self.t: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.w: E = None
        self.r: J = None
        self.p: I = None
        self.t: B = None
        self.y: H = None
        self.x: F = None
        self.z: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.w: B = None
        self.x: C = None
        self.y: J = None
        self.s: J = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.v: B = None
        self.o: G = None
        self.u: G = None
        self.p: A = None
        self.t: I = None
        self.y: A = None
        self.q: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: I = None
        self.p: G = None
        self.w: D = None
        self.x: G = None
        self.v: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: C = None
        self.p: A = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.x: A = None
        self.y: I = None
        self.q: F = None
        self.p: D = None
        self.r: E = None
        self.u: E = None
        self.t: A = None
        self.txt = txt

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

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