<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_context_from_xlsx(self):
 """ Get context from an Excel file """

        if re.search('^(http|https)://', self.project.CONTEXT_SOURCE_FILE):
            resp = requests.get(self.project.CONTEXT_SOURCE_FILE)
            content = resp.content
        else:
            try:
                with open(self.project.CONTEXT_SOURCE_FILE) as xlsxfile:
                    content = xlsxfile.read()
            except IOError:
                filepath = "%s/%s" % (
                    os.path.abspath(self.path),
                    self.project.CONTEXT_SOURCE_FILE)
                with open(filepath) as xlsxfile:
                    content = xlsxfile.read()

        data = process_xlsx(content)
        if 'values' in data:
            data = copy_global_values(data)

        return data