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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_issuer(site_url=None, request=None):
 """ Construct the issuer full url. Basically is the site url with some path appended. """

    site_url = get_site_url(site_url=site_url, request=request)
    path = reverse('oidc_provider:provider-info') \
        .split('/.well-known/openid-configuration')[0]
    issuer = site_url + path

    return str(issuer)