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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 cache_dest(self, url, saltenv='base', cachedir=None):
        '''
        Return the expected cache location for the specified URL and
        environment.
        '''
        proto = urlparse(url).scheme

        if proto == '':
            # Local file path
            return url

        if proto == 'salt':
            url, senv = salt.utils.url.parse(url)
            if senv:
                saltenv = senv
            return salt.utils.path.join(
                self.opts['cachedir'],
                'files',
                saltenv,
                url.lstrip('|/'))

        return self._extrn_path(url, saltenv, cachedir=cachedir)