<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def parse_relationship(document, xmlcontent, rel_type):
 """Parse relationship document. Relationships hold information like external or internal references for links. Relationships are placed in file '_rels/document.xml.rels'. """


    doc = etree.fromstring(xmlcontent)

    for elem in doc:
        if elem.tag == _name('{{{pr}}}Relationship'):
            rel = {'target': elem.attrib['Target'],
                   'type': elem.attrib['Type'],
                   'target_mode': elem.attrib.get('TargetMode', 'Internal')}

            document.relationships[rel_type][elem.attrib['Id']] = rel