def test_1(): assert calculate('2*2') - 4 < 0.0001
def test_2(): assert calculate('whats the mass of moon')
def test_4(): assert calculate('im too awesome').startswith('Too bad')
def test_5(): assert calculate('berkeley california').count('population') == 3
def test_3(): assert calculate('mass of the sun in kg').startswith('1.988435')
def test_2(): assert calculate('4**3+7*8') == 120
def test_3(): assert abs(6.-calculate('1+2+3'))<0.001
def test_1(): assert abs(4.-calculate('2**2'))<0.001
def test_4(): assert calculate('density of water')