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

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.q: C = None
        self.u: H = None
        self.w: C = None
        self.v: J = None
        self.r: H = None
        self.s: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.u: G = None
        self.z: F = None
        self.p: F = None
        self.t: H = None
        self.q: C = None
        self.y: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: J = None
        self.t: I = None
        self.v: F = None
        self.p: C = None
        self.z: B = None
        self.x: D = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: B = None
        self.p: G = None
        self.o: E = None
        self.r: B = None
        self.u: C = None
        self.q: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: H = None
        self.q: C = None
        self.u: H = None
        self.w: C = None
        self.v: J = None
        self.r: H = None
        self.s: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.u: G = None
        self.z: F = None
        self.p: F = None
        self.t: H = None
        self.q: C = None
        self.y: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: J = None
        self.t: I = None
        self.v: F = None
        self.p: C = None
        self.z: B = None
        self.x: D = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: B = None
        self.p: G = None
        self.o: E = None
        self.r: B = None
        self.u: C = None
        self.q: G = None
        self.txt = txt

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

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