def __init__(self, context, package_requests, package_paths, package_filter=None,<EOL>package_orderers=None, timestamp=<NUM_LIT:0>, callback=None, building=False,<EOL>verbosity=False, buf=None, package_load_callback=None, caching=True,<EOL>suppress_passive=False, print_stats=False):
self.context = context<EOL>self.package_requests = package_requests<EOL>self.package_paths = package_paths<EOL>self.timestamp = timestamp<EOL>self.callback = callback<EOL>self.package_orderers = package_orderers<EOL>self.package_load_callback = package_load_callback<EOL>self.building = building<EOL>self.verbosity = verbosity<EOL>self.caching = caching<EOL>self.buf = buf<EOL>self.suppress_passive = suppress_passive<EOL>self.print_stats = print_stats<EOL>if package_orderers:<EOL><INDENT>sha1s = '<STR_LIT>'.join(x.sha1 for x in package_orderers)<EOL>self.package_orderers_hash = sha1(sha1s).hexdigest()<EOL><DEDENT>else:<EOL><INDENT>self.package_orderers_hash = '<STR_LIT>'<EOL><DEDENT>if package_filter:<EOL><INDENT>self.package_filter_hash = package_filter.sha1<EOL><DEDENT>else:<EOL><INDENT>self.package_filter_hash = '<STR_LIT>'<EOL><DEDENT>if self.timestamp:<EOL><INDENT>if package_filter:<EOL><INDENT>self.package_filter = package_filter.copy()<EOL><DEDENT>else:<EOL><INDENT>self.package_filter = PackageFilterList()<EOL><DEDENT>rule = TimestampRule.after(self.timestamp)<EOL>self.package_filter.add_exclusion(rule)<EOL><DEDENT>else:<EOL><INDENT>self.package_filter = package_filter<EOL><DEDENT>self.status_ = ResolverStatus.pending<EOL>self.resolved_packages_ = None<EOL>self.failure_description = None<EOL>self.graph_ = None<EOL>self.from_cache = False<EOL>self.memcached_servers = config.memcached_uri if config.resolve_caching else None<EOL>self.solve_time = <NUM_LIT:0.0>  <EOL>self.load_time = <NUM_LIT:0.0>   <EOL>self._print = config.debug_printer("<STR_LIT>")<EOL>
Create a Resolver.

        Args:
            package_requests: List of Requirement objects representing the
                request.
            package_paths: List of paths to search for pkgs.
            package_filter (`PackageFilterList`): Package filter.
            package_orderers (list of `PackageOrder`): Custom package ordering.
            callback: See `Solver`.
            package_load_callback: If not None, this callable will be called
                prior to each package being loaded. It is passed a single
                `Package` object.
            building: True if we're resolving for a build.
            caching: If True, cache(s) may be used to speed the resolve. If
                False, caches will not be used.
            print_stats (bool): If true, print advanced solver stats at the end.