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

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

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

class D:
    def __init__(self, txt: str):
        self.s: J = None
        self.x: H = None
        self.u: A = None
        self.w: J = None
        self.z: A = None
        self.y: B = None
        self.p: B = None
        self.o: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: B = None
        self.z: H = None
        self.u: A = None
        self.o: B = None
        self.v: I = None
        self.x: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: D = None
        self.w: D = None
        self.s: F = None
        self.t: F = None
        self.r: D = None
        self.o: E = None
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.v: E = None
        self.r: B = None
        self.z: I = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: J = None
        self.x: H = None
        self.u: A = None
        self.w: J = None
        self.z: A = None
        self.y: B = None
        self.p: B = None
        self.o: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: B = None
        self.z: H = None
        self.u: A = None
        self.o: B = None
        self.v: I = None
        self.x: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: D = None
        self.w: D = None
        self.s: F = None
        self.t: F = None
        self.r: D = None
        self.o: E = None
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.v: E = None
        self.r: B = None
        self.z: I = None
        self.s: F = None
        self.txt = txt

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

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

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

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