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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_context(self, publish=False):
 """ Use optional CONTEXT_SOURCE_FILE setting to determine data source. Return the parsed data. Can be an http|https url or local file. Supports csv and excel files. """

        context = self.project.DEFAULT_CONTEXT
        try:
            file = self.project.CONTEXT_SOURCE_FILE
            # CSV
            if re.search(r'(csv|CSV)$', file):
                context.update(self.get_context_from_csv())
            # Excel
            if re.search(r'(xlsx|XLSX|xls|XLS)$', file):
                context.update(self.get_context_from_xlsx())
        except AttributeError:
            context.update(self.get_context_from_gdoc())

        return context