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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 image(alt_text, link_url, title=""):
 """Return an inline image. Keyword arguments: title -- Specify the title of the image, as seen when hovering over it. '![This is an image](https://tinyurl.com/bright-green-tree)' '![This is an image](https://tinyurl.com/bright-green-tree) "tree"' """

    image_string = "![" + esc_format(alt_text) + "](" + link_url + ")"
    if title:
        image_string += ' "' + esc_format(title) + '"'
    return image_string