import pandas as pd
import io

print("Pandas version: ", pd.__version__)

def xml2df(xml_file):
    with open(xml_file, "r") as F:
        xml_data = F.read()
    return pd.read_xml(io.StringIO(xml_data), parser="etree", xpath=".//component-class//feature-value")

if __name__ == "__main__":
    df = xml2df("test_data.tcx")
    df.assign(counter = lambda df: df.groupby('.//component/name').cumcount())

    print(df)