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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 clean_file(configuration, filename):
 """ Strips out the warning from a translated po file about being an English source file. Replaces warning with a note about coming from Transifex. """

    pofile = polib.pofile(filename)

    if pofile.header.find(EDX_MARKER) != -1:
        new_header = get_new_header(configuration, pofile)
        new = pofile.header.replace(EDX_MARKER, new_header)
        pofile.header = new
        pofile.save()