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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 tag(placeholders):
 """ Tag the file at podpath with the information in podcast and entry """

    # We first recover the name of the file to be tagged...
    template = placeholders.feed.retrieve_config("file_to_tag", "{filename}")
    filename = substitute_placeholders(template, placeholders)
    podpath = os.path.join(placeholders.directory, filename)
    # ... and this is it

    # now we create a dictionary of tags and values
    tagdict = placeholders.feed.defaulttagdict  # these are the defaults
    try:  # We do as if there was a section with potential tag info
        feedoptions = placeholders.feed.config.options(placeholders.name)
        # this monstruous concatenation of classes... surely a bad idea.
        tags = [[option.replace("tag_", ""), placeholders.feed.config[
            placeholders.name][option]] for option in feedoptions if "tag_" in
                option]  # these are the tags to be filled
        if tags:
            for tag in tags:
                tagdict[tag[0]] = tag[1]
    except configparser.NoSectionError:
        pass
    for tag in tagdict:
        metadata = substitute_placeholders(
            tagdict[tag], placeholders)
        if metadata:
            stagger.util.set_frames(podpath, {tag: metadata})
        else:
            stagger.util.remove_frames(podpath, tag)