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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 urls_from_file_tree(template_dir):
 """Generates a list of URL strings that would match each staticflatpage."""

    urls = []  # keep a list of of all the files/paths

    # Should be somethign like:
    # /path/to/myproject/templates/staticflatpages
    root_dir = join(template_dir, 'staticflatpages')

    for root, dirs, files in walk(template_dir):
        # Only do this for the ``staticflatpages`` directory or sub-directories
        if "staticflatpages" in root:
            root = root.replace(root_dir, '')
            for f in files:
                path = join(root, f)
                path = _format_as_url(path)
                urls.append(path)
    return urls