class A:
    def __init__(self, txt: str):
        self.z: J = None
        self.x: H = None
        self.r: G = None
        self.t: G = None
        self.v: D = None
        self.o: H = None
        self.s: I = None
        self.u: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: J = None
        self.v: I = None
        self.r: D = None
        self.y: I = None
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: A = None
        self.v: E = None
        self.t: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: E = None
        self.p: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: J = None
        self.v: I = None
        self.r: D = None
        self.y: I = None
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: A = None
        self.v: E = None
        self.t: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: E = None
        self.p: C = None
        self.txt = txt

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

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