''' Q2: Given a list x as input, return a list with every other element of x
>>> f([1,2,3,4,5]) 
[1,3,5]
>>> f([-1,0,1])
[-1, 1]
>>> f([-1])
[-1]
>>> f([])
[]
'''

def f(x):
    # Your Code Here!
    pass

if __name__ == '__main__':
    import doctest
    doctest.testmod()