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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.s: H = None
        self.q: C = None
        self.t: C = None
        self.u: E = None
        self.w: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: I = None
        self.u: D = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.p: C = None
        self.w: B = None
        self.r: D = None
        self.t: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.o: A = None
        self.p: E = None
        self.s: H = None
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.r: F = None
        self.w: A = None
        self.s: A = None
        self.q: B = None
        self.v: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.s: H = None
        self.q: C = None
        self.t: C = None
        self.u: E = None
        self.w: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: I = None
        self.u: D = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: D = None
        self.p: C = None
        self.w: B = None
        self.r: D = None
        self.t: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: C = None
        self.o: A = None
        self.p: E = None
        self.s: H = None
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: G = None
        self.r: F = None
        self.w: A = None
        self.s: A = None
        self.q: B = None
        self.v: D = None
        self.txt = txt

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

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

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