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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def remove(image, mask=None, iterations=1):
    '''Turn 1 pixels to 0 if their 4-connected neighbors are all 0
    
    ? 1 ?     ? 1 ?
    1 1 1  -> 1 0 1
    ? 1 ?     ? 1 ?
    '''
    global remove_table
    if mask is None:
        masked_image = image
    else:
        masked_image = image.astype(bool).copy()
        masked_image[~mask] = False
    result = table_lookup(masked_image, remove_table, False)
    if not mask is None:
        result[~mask] = image[~mask]
    return result