class A:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: E = None
        self.q: D = None
        self.r: G = None
        self.o: E = None
        self.u: B = None
        self.t: E = None
        self.v: B = None
        self.y: B = None
        self.p: I = 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.v: J = None
        self.r: E = None
        self.w: D = None
        self.y: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: H = None
        self.w: G = None
        self.t: C = None
        self.r: B = None
        self.u: D = None
        self.o: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: I = None
        self.x: A = None
        self.txt = txt

d = A("d")
g = B("g")
b = C("b")
c = D("c")
l = E("l")
f = F("f")
a = G("a")
e = H("e")
m = I("m")
k = J("k")

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: H = None
        self.w: G = None
        self.t: C = None
        self.r: B = None
        self.u: D = None
        self.o: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: I = None
        self.x: A = None
        self.txt = txt

d = A("d")
g = B("g")
b = C("b")
c = D("c")
l = E("l")
f = F("f")
a = G("a")
e = H("e")
m = I("m")
k = J("k")

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