def activate_user(UserId=None):
    """
    Activates the specified user. Only active users can access Amazon WorkDocs.
    See also: AWS API Documentation
    
    
    :example: response = client.activate_user(
        UserId='string'
    )
    
    
    :type UserId: string
    :param UserId: [REQUIRED]
            The ID of the user.
            

    :rtype: dict
    :return: {
        'User': {
            'Id': 'string',
            'Username': 'string',
            'EmailAddress': 'string',
            'GivenName': 'string',
            'Surname': 'string',
            'OrganizationId': 'string',
            'RootFolderId': 'string',
            'RecycleBinFolderId': 'string',
            'Status': 'ACTIVE'|'INACTIVE'|'PENDING',
            'Type': 'USER'|'ADMIN',
            'CreatedTimestamp': datetime(2015, 1, 1),
            'ModifiedTimestamp': datetime(2015, 1, 1),
            'TimeZoneId': 'string',
            'Locale': 'en'|'fr'|'ko'|'de'|'es'|'ja'|'ru'|'zh_CN'|'zh_TW'|'pt_BR'|'default',
            'Storage': {
                'StorageUtilizedInBytes': 123,
                'StorageRule': {
                    'StorageAllocatedInBytes': 123,
                    'StorageType': 'UNLIMITED'|'QUOTA'
                }
            }
        }
    }
    
    
    """
    pass
