def test_dirichlet_eta():
x = Symbol("x")
e1 = sympy.dirichlet_eta(sympy.Symbol("x"))
e2 = dirichlet_eta(x)
assert sympify(e1) == e2
assert e2._sympy_() == e1
def test_dirichlet_eta():
assert dirichlet_eta(0) == Rational(1, 2)
assert dirichlet_eta(-1) == Rational(1, 4)
assert dirichlet_eta(1) == log(2)
assert dirichlet_eta(2) == pi**2 / 12
assert dirichlet_eta(4) == pi**4 * Rational(7, 720)