def filter_stmts(content, classes):
    """ Pop and return classes instances from content.
    """
    stmts = []
    indices = []
    for i in range(len(content)):
        stmt = content[i]
        if isinstance(stmt, classes):
            stmts.append(stmt)
            indices.append(i)
    indices.reverse()
    for i in indices:
        del content[i]
    return stmts