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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_ppas_from_file(file_name, update=True):
 """Add personal package archive from a file list."""


    for ppa in _read_lines_from_file(file_name):
        add_ppa(ppa, update=False)
    if update:
        update_apt_sources()