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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 _utf_strip_bom(self, encoding):
 """Return an encoding that will ignore the BOM."""


        if encoding is None:
            pass
        elif encoding.lower() == 'utf-8':
            encoding = 'utf-8-sig'
        elif encoding.lower().startswith('utf-16'):
            encoding = 'utf-16'
        elif encoding.lower().startswith('utf-32'):
            encoding = 'utf-32'
        return encoding