"""Fictional library versions, not a report about a real package."""
def library_v1(text):return text.strip()
def library_v2(text):return str(int(text.strip()))
def account_adapter(text):
    value=text.strip()
    if not value or any(c not in '0123456789' for c in value):raise ValueError('invalid account reference')
    return value
CASES=[('0017','0017'),(' 0017 ','0017'),('17','17')]
if __name__=='__main__':
    for raw,expected in CASES:
        assert library_v1(raw)==expected
        assert account_adapter(raw)==expected
        print(repr(raw),'expected',expected,'v1',library_v1(raw),'v2',library_v2(raw),'adapter',account_adapter(raw))
    assert library_v2('0017')!='0017'
    try:account_adapter('17x')
    except ValueError:pass
    else:raise AssertionError('bad reference accepted')
    print('8/8 assertions passed. Authored identifier contract; no real dependency regression is claimed.')