class A:
    def __init__(self, txt: str):
        self.v: B = None
        self.p: I = None
        self.q: I = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.x: F = None
        self.w: J = None
        self.v: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: I = None
        self.v: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: A = None
        self.x: A = None
        self.v: C = None
        self.w: D = None
        self.p: H = None
        self.s: A = None
        self.u: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: E = None
        self.z: J = None
        self.o: C = None
        self.w: F = None
        self.s: G = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: H = None
        self.x: C = None
        self.p: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: H = None
        self.q: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.x: F = None
        self.w: J = None
        self.v: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: I = None
        self.v: F = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.z: A = None
        self.x: A = None
        self.v: C = None
        self.w: D = None
        self.p: H = None
        self.s: A = None
        self.u: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: E = None
        self.z: J = None
        self.o: C = None
        self.w: F = None
        self.s: G = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: H = None
        self.x: C = None
        self.p: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: H = None
        self.q: D = None
        self.txt = txt

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

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