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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 _need_update(self, project_name, updatetime=None, md5sum=None):
        '''Check if project_name need update'''
        if project_name not in self.projects:
            return True
        elif md5sum and md5sum != self.projects[project_name]['info'].get('md5sum'):
            return True
        elif updatetime and updatetime > self.projects[project_name]['info'].get('updatetime', 0):
            return True
        elif time.time() - self.projects[project_name]['load_time'] > self.RELOAD_PROJECT_INTERVAL:
            return True
        return False