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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 read_html_file(filename):
 """Reads the contents of an html file in the css directory @return: Contents of the specified file """

    with open(os.path.join(get_static_directory(), 'html/{filename}'.format(filename=filename))) as f:
        contents = f.read()
    return contents