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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 patch(self, body, raise_exc=True, headers=False, files=None):
        '''Performs an HTTP PATCH to the server. This is a
        non-idempotent call that may update all or a portion of the
        resource this navigator is pointing to. The format of the
        patch body is up to implementations.

        `body` may either be a string or a dictionary representing json
        `headers` are additional headers to send in the request
        '''
        return self._request(PATCH, body, raise_exc, headers, files)