Update or fill the fields parameters depending on command code. Both cmd and drAppId can be provided  # noqa: E501
       in string or int format.

def getCmdParams(cmd, request, **fields):
    """Update or fill the fields parameters depending on command code. Both cmd and drAppId can be provided  # noqa: E501
       in string or int format."""
    drCode = None
    params = None
    drAppId = None
    # Fetch the parameters if cmd is found in dict
    if isinstance(cmd, int):
        drCode = cmd    # Enable to craft commands with non standard code
        if cmd in DR_cmd_def:
            params = DR_cmd_def[drCode]
        else:
            params = ('Unknown', 'UK', {0: (128, 0)})
            warning(
                'No Diameter command with code %d found in DR_cmd_def dictionary' %  # noqa: E501
                cmd)
    else:  # Assume command is a string
        if len(cmd) > 3:     # Assume full command name given
            fpos = 0
        else:         # Assume abbreviated name is given and take only the first two letters  # noqa: E501
            cmd = cmd[:2]
            fpos = 1
        for k, f in DR_cmd_def.items():
            if f[fpos][:len(
                    cmd)] == cmd:   # Accept only a prefix of the full name
                drCode = k
                params = f
                break
        if not drCode:
            warning(
                'Diameter command with name %s not found in DR_cmd_def dictionary.' %  # noqa: E501
                cmd)
            return (fields, 'Unknown')
    # The drCode is set/overridden in any case
    fields['drCode'] = drCode
    # Processing of drAppId
    if 'drAppId' in fields:
        val = fields['drAppId']
        if isinstance(val, str):   # Translate into application Id code
            found = False
            for k, v in six.iteritems(AppIDsEnum):
                if v.find(val) != -1:
                    drAppId = k
                    fields['drAppId'] = drAppId
                    found = True
                    break
            if not found:
                del(fields['drAppId'])
                warning(
                    'Application ID with name %s not found in AppIDsEnum dictionary.' %  # noqa: E501
                    val)
                return (fields, 'Unknown')
        else:   # Assume type is int
            drAppId = val
    else:  # Application Id shall be taken from the params found based on cmd
        drAppId = next(iter(params[2]))   # The first record is taken
        fields['drAppId'] = drAppId
    # Set the command name
    name = request and params[0] + '-Request' or params[0] + '-Answer'
    # Processing of flags (only if not provided manually)
    if 'drFlags' not in fields:
        if drAppId in params[2]:
            flags = params[2][drAppId]
            fields['drFlags'] = request and flags[0] or flags[1]
    return (fields, name)