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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 get_host(environ):
 """Return the real host for the given WSGI environment. This takes care of the `X-Forwarded-Host` header. :param environ: the WSGI environment to get the host of. """

    scheme = environ.get('wsgi.url_scheme')
    if 'HTTP_X_FORWARDED_HOST' in environ:
        result = environ['HTTP_X_FORWARDED_HOST']
    elif 'HTTP_HOST' in environ:
        result = environ['HTTP_HOST']
    else:
        result = environ['SERVER_NAME']
        if (scheme, str(environ['SERVER_PORT'])) not \
           in (('https', '443'), ('http', '80')):
            result += ':' + environ['SERVER_PORT']
    if result.endswith(':80') and scheme == 'http':
        result = result[:-3]
    elif result.endswith(':443') and scheme == 'https':
        result = result[:-4]
    return result