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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_boundary(self, failobj=None):
 """Return the boundary associated with the payload if present. The boundary is extracted from the Content-Type header's `boundary' parameter, and it is unquoted. """

        missing = object()
        boundary = self.get_param('boundary', missing)
        if boundary is missing:
            return failobj
        # RFC 2046 says that boundaries may begin but not end in w/s
        return utils.collapse_rfc2231_value(boundary).rstrip()