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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def list_locks(root=None):
    '''
    List current package locks.

    root
        operate on a different root directory.

    Return a dict containing the locked package with attributes::

        {'<package>': {'case_sensitive': '<case_sensitive>',
                       'match_type': '<match_type>'
                       'type': '<type>'}}

    CLI Example:

    .. code-block:: bash

        salt '*' pkg.list_locks
    '''
    locks = {}
    _locks = os.path.join(root, os.path.relpath(LOCKS, os.path.sep)) if root else LOCKS
    try:
        with salt.utils.files.fopen(_locks) as fhr:
            items = salt.utils.stringutils.to_unicode(fhr.read()).split('\n\n')
            for meta in [item.split('\n') for item in items]:
                lock = {}
                for element in [el for el in meta if el]:
                    if ':' in element:
                        lock.update(dict([tuple([i.strip() for i in element.split(':', 1)]), ]))
                if lock.get('solvable_name'):
                    locks[lock.pop('solvable_name')] = lock
    except IOError:
        pass
    except Exception:
        log.warning('Detected a problem when accessing %s', _locks)

    return locks