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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 merge_headers(header_map_list):
 """ Helper function for combining multiple header maps into one. :param list(dict) header_map_list: list of maps :rtype: dict """

    headers = {}
    for header_map in header_map_list:
        if header_map:
            headers.update(header_map)
    return headers