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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 bridge(image, mask=None, iterations = 1):
    '''Fill in pixels that bridge gaps.
    
    1 0 0    1 0 0
    0 0 0 -> 0 1 0
    0 0 1    0 0 1
    '''
    global bridge_table
    if mask is None:
        masked_image = image
    else:
        masked_image = image.astype(bool).copy()
        masked_image[~mask] = False
    result = table_lookup(masked_image, bridge_table, False, iterations)
    if not mask is None:
        result[~mask] = image[~mask]
    return result