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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_vault_connection():
    '''
    Get the connection details for calling Vault, from local configuration if
    it exists, or from the master otherwise
    '''
    def _use_local_config():
        log.debug('Using Vault connection details from local config')
        try:
            if __opts__['vault']['auth']['method'] == 'approle':
                verify = __opts__['vault'].get('verify', None)
                if _selftoken_expired():
                    log.debug('Vault token expired. Recreating one')
                    # Requesting a short ttl token
                    url = '{0}/v1/auth/approle/login'.format(__opts__['vault']['url'])
                    payload = {'role_id': __opts__['vault']['auth']['role_id']}
                    if 'secret_id' in __opts__['vault']['auth']:
                        payload['secret_id'] = __opts__['vault']['auth']['secret_id']
                    response = requests.post(url, json=payload, verify=verify)
                    if response.status_code != 200:
                        errmsg = 'An error occured while getting a token from approle'
                        raise salt.exceptions.CommandExecutionError(errmsg)
                    __opts__['vault']['auth']['token'] = response.json()['auth']['client_token']
            if __opts__['vault']['auth']['method'] == 'wrapped_token':
                verify = __opts__['vault'].get('verify', None)
                if _wrapped_token_valid():
                    url = '{0}/v1/sys/wrapping/unwrap'.format(__opts__['vault']['url'])
                    headers = {'X-Vault-Token': __opts__['vault']['auth']['token']}
                    response = requests.post(url, headers=headers, verify=verify)
                    if response.status_code != 200:
                        errmsg = 'An error occured while unwrapping vault token'
                        raise salt.exceptions.CommandExecutionError(errmsg)
                    __opts__['vault']['auth']['token'] = response.json()['auth']['client_token']
            return {
                'url': __opts__['vault']['url'],
                'token': __opts__['vault']['auth']['token'],
                'verify': __opts__['vault'].get('verify', None)
            }
        except KeyError as err:
            errmsg = 'Minion has "vault" config section, but could not find key "{0}" within'.format(err.message)
            raise salt.exceptions.CommandExecutionError(errmsg)

    if 'vault' in __opts__ and __opts__.get('__role', 'minion') == 'master':
        if 'id' in __grains__:
            log.debug('Contacting master for Vault connection details')
            return _get_token_and_url_from_master()
        else:
            return _use_local_config()
    elif any((__opts__['local'], __opts__['file_client'] == 'local', __opts__['master_type'] == 'disable')):
        return _use_local_config()
    else:
        log.debug('Contacting master for Vault connection details')
        return _get_token_and_url_from_master()