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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 requestedFormat(request,acceptedFormat):
 """Return the response format requested by client Client could specify requested format using: (options are processed in this order) - `format` field in http request - `Accept` header in http request Example: chooseFormat(request, ['text/html','application/json']) Args: acceptedFormat: list containing all the accepted format Returns: string: the user requested mime-type (if supported) Raises: ValueError: if user request a mime-type not supported """

        if 'format' in request.args:
            fieldFormat = request.args.get('format')
            if fieldFormat not in acceptedFormat:
                raise ValueError("requested format not supported: "+ fieldFormat)
            return fieldFormat
        else:
            return request.accept_mimetypes.best_match(acceptedFormat)