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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 param_show(param=None):
    '''
    Show params of varnish cache

    CLI Example:

    .. code-block:: bash

        salt '*' varnish.param_show param
    '''
    ret = _run_varnishadm('param.show', [param])
    if ret['retcode']:
        return False
    else:
        result = {}
        for line in ret['stdout'].split('\n'):
            m = re.search(r'^(\w+)\s+(.*)$', line)
            result[m.group(1)] = m.group(2)
            if param:
                # When we ask to varnishadm for a specific param, it gives full
                # info on what that parameter is, so we just process the first
                # line and we get out of the loop
                break
        return result