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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 full_width_svg(url, width, height, alt_text=None):
    ''' Helper to render an SVG that will size to fill
        its element while keeping its dimentions.

        '''

    return {
        'ratio': str((float(height)/float(width))*100)[:2],
        'url': url,
        'alt_text': alt_text
    }