Traceback (most recent call last):
  File "/trytond/protocols/jsonrpc.py", line 108, in _marshaled_dispatch
    response['result'] = dispatch_method(method, params)
  File "/trytond/protocols/jsonrpc.py", line 147, in _dispatch
    res = dispatch(*args)
  File "/trytond/protocols/dispatcher.py", line 155, in dispatch
    res = getattr(obj, method)(*args_without_context, **kargs)
  File "/trytond/modules/account_invoice/invoice.py", line 2148, in execute
    res = super(InvoiceReport, self).execute(ids, datas)
  File "/trytond/report/report.py", line 134, in execute
    type, data = self.parse(action_report, objects, datas, {})
  File "/trytond/modules/account_invoice/invoice.py", line 2176, in parse
    localcontext)
  File "/trytond/report/report.py", line 180, in parse
    content_io.write(report.report_content)
TypeError: char buffer type not available