But i want to do bulk insert using excel file.
How to pass the excel file in payload and insert the record in translation manager for different gateways at same time?
Don't, you'll run into headaches. Instead, parse the file in whatever event where you are accessing it, and build some type of data structure to send as the payload.
For instance I would be tempted to build a dictionary where the English is the key.
def handleMessage(payload):
translations = payload['Translations']
for english,vals in translations.iteritems():
system.util.modifyTranslation(english,vals['Translated_lang'],vals['Language_code'])
Note: Depending on how many of these you need to do, you may need to consider breaking the file into manageable chunks.