code: public function buildChargeFromTransaction( $sTxnID ) {
  		$oCharge = new Freeagent\DataWrapper\ChargeVO();
  
  		try {
  			$oDets = $this->getTxnChargeDetails( $sTxnID );
  
  			$oCharge->setId( $sTxnID )
  					->setGateway( 'paypalexpress' )
  					->setPaymentTerms( 1 )
  					->setAmount_Gross( $oDets->GrossAmount->value )
  					->setAmount_Fee( $oDets->FeeAmount->value )
  					->setAmount_Net( $oDets->GrossAmount->value - $oDets->FeeAmount->value )
  					->setDate( strtotime( $oDets->PaymentDate ) )
  					->setCurrency( $oDets->GrossAmount->currencyID );
  		}
  		catch ( \Exception $oE ) {
  		}
  
  		return $oCharge;
  	}
docs: This needs to be extended to add the Invoice Item details.
  @param string $sTxnID a Stripe Charge ID
  @return Freeagent\DataWrapper\ChargeVO
  @throws \Exception