def merge_two_dicts(x, y):
    """Given two dicts x and y, merge them into a new dict z, as a shallow copy
    
    Parameters
    ----------
    x: `dict()`
    y: `dict()`
    
    Returns
    -------
    z: `dict()`
    """
    z = x.copy()
    z.update(y)

    return z