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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 is_installed(path, user=None):
    '''
    Check if wordpress is installed and setup

    path
        path to wordpress install location

    user
        user to run the command as

    CLI Example:

    .. code-block:: bash

        salt '*' wordpress.is_installed /var/www/html apache
    '''
    retcode = __salt__['cmd.retcode']((
        'wp --path={0} core is-installed'
    ).format(path), runas=user)
    if retcode == 0:
        return True
    return False