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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 xml(self, indent = ""):
 """Serialise provenance data to XML. This is included in CLAM Metadata files"""

        xml = indent + "<provenance type=\"clam\" id=\""+self.serviceid+"\" name=\"" +self.servicename+"\" url=\"" + self.serviceurl+"\" outputtemplate=\""+self.outputtemplate_id+"\" outputtemplatelabel=\""+self.outputtemplate_label+"\" timestamp=\""+str(self.timestamp)+"\">"
        for filename, metadata in self.inputfiles:
            xml += indent + " <inputfile name=\"" + clam.common.util.xmlescape(filename) + "\">"
            xml += metadata.xml(indent + " ") + "\n"
            xml += indent +  " </inputfile>\n"
        if self.parameters:
            xml += indent + " <parameters>\n"
            if isinstance(self.parameters, dict):
                parameters = self.parameters.values()
            elif isinstance(self.parameters, list):
                parameters = self.parameters
            for parameter in parameters:
                xml += parameter.xml(indent +"  ") + "\n"
            xml += indent + " </parameters>\n"
        xml += indent + "</provenance>"
        return xml