def remove_security_tokens(uri, tokens = {})
      validate_presence_of uri, 'Channel URI'
      validate_presence_of tokens, 'Security Tokens'

      message = { 'ChannelURI' => uri,
                  'SecurityToken' => security_token_hash(tokens) }

      @client.call(:remove_security_tokens, message: message)

      return true
    end
def remove_security_tokens(uri, tokens = {})
      validate_presence_of uri, 'Channel URI'
      validate_presence_of tokens, 'Security Tokens'

      message = { 'ChannelURI' => uri,
                  'SecurityToken' => security_token_hash(tokens) }

      @client.call(:remove_security_tokens, message: message)

      return true
    end
Removes security tokens from a channel.

 @param uri [String] the channel URI
 @param tokens [Hash] username password pairs, e.g. {'u1' => 'p1', 'u2' => 'p2'}
 @return [void]
 @raise [ArgumentError] if uri is blank or no tokens are provided