<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def element(self, tag_path, test=None, **attributes):

 """given a tag in xpath form and optional attributes, find the element in self.root or return a new one."""

        xpath = tag_path
        tests = ["@%s='%s'" % (k, attributes[k]) for k in attributes]
        if test is not None:
            tests.insert(0, test)
        if len(tests) > 0:
            xpath += "[%s]" % ' and '.join(tests)
        e = self.find(self.root, xpath)
        if e is None:
            tag = tag_path.split('/')[-1].split('[')[0]
            tagname = tag.split(':')[-1]
            if ':' in tag:
                nstag = tag.split(':')[0]
                tag = "{%s}%s" % (self.NS[nstag], tagname)
            e = etree.Element(tag, **attributes)
        return e