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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 add_it(workbench, file_list, labels):
 """Add the given file_list to workbench as samples, also add them as nodes. Args: workbench: Instance of Workbench Client. file_list: list of files. labels: labels for the nodes. Returns: A list of md5s. """

    md5s = []
    for filename in file_list:
        if filename != '.DS_Store':
            with open(filename, 'rb') as pe_file:
                base_name = os.path.basename(filename)
                md5 = workbench.store_sample(pe_file.read(), base_name, 'exe')
                workbench.add_node(md5, md5[:6], labels)
                md5s.append(md5)
    return md5s