Trying to parse an XML returns an error

C:\Users\funim\Downloads\parsexml>python parse_uspto_xml/parse_patent.py ipg150106.xml

Error : C:\Users\funim\Downloads\parsexml\parse_uspto_xml\parse_patent.py:224: SyntaxWarning: invalid escape sequence '\s'

"\s?(?P[0-9]{1,4})" C:\Users\funim\Downloads\parsexml\parse_uspto_xml\parse_patent.py:225: SyntaxWarning: invalid escape sequence '\s'
"\s?/\s?"

What should I do?

lettergram / parse-uspto-xml