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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 profile(request):
    '''
    Get or set user profile.
    '''
    serializer_class = registration_settings.PROFILE_SERIALIZER_CLASS
    if request.method in ['POST', 'PUT', 'PATCH']:
        partial = request.method == 'PATCH'
        serializer = serializer_class(
            instance=request.user,
            data=request.data,
            partial=partial,
        )
        serializer.is_valid(raise_exception=True)
        serializer.save()
    else:  # request.method == 'GET':
        serializer = serializer_class(instance=request.user)

    return Response(serializer.data)