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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 load_var_files(opt, p_obj=None):
 """Load variable files, merge, return contents"""

    obj = {}
    if p_obj:
        obj = p_obj

    for var_file in opt.extra_vars_file:
        LOG.debug("loading vars from %s", var_file)
        obj = merge_dicts(obj.copy(), load_var_file(var_file, obj))

    return obj