parameters: (self, resolution, candidates, information)
docstring: Produce a sort key for given requirement based on preference.
  
          The preference is defined as "I think this requirement should be
          resolved first". The lower the return value is, the more preferred
          this group of arguments is.
  
          :param resolution: Currently pinned candidate, or `None`.
          :param candidates: An iterable of possible candidates.
          :param information: A list of requirement information.
  
          The `candidates` iterable's exact type depends on the return type of
          `find_matches()`. A sequence is passed-in as-is if possible. If it
          returns a callble, the iterator returned by that callable is passed
          in here.
  
          Each element in `information` is a named tuple with two entries:
  
          * `requirement` specifies a requirement contributing to the current
            candidate list.
          * `parent` specifies the candidate that provides (dependend on) the
            requirement, or `None` to indicate a root requirement.
  
          The preference could depend on a various of issues, including (not
          necessarily in this order):
  
          * Is this package pinned in the current resolution result?
          * How relaxed is the requirement? Stricter ones should probably be
            worked on first? (I don't know, actually.)
          * How many possibilities are there to satisfy this requirement? Those
            with few left should likely be worked on first, I guess?
          * Are there any known conflicts for this requirement? We should
            probably work on those with the most known conflicts.
  
          A sortable value should be returned (this will be used as the `key`
          parameter of the built-in sorting function). The smaller the value is,
          the more preferred this requirement is (i.e. the sorting function
          is called with `reverse=False`).
docstring_summary: Produce a sort key for given requirement based on preference.
docstring_tokens: Produce a sort key for given requirement based on preference .
function: def get_preference(self, resolution, candidates, information):
          """Produce a sort key for given requirement based on preference.
  
          The preference is defined as "I think this requirement should be
          resolved first". The lower the return value is, the more preferred
          this group of arguments is.
  
          :param resolution: Currently pinned candidate, or `None`.
          :param candidates: An iterable of possible candidates.
          :param information: A list of requirement information.
  
          The `candidates` iterable's exact type depends on the return type of
          `find_matches()`. A sequence is passed-in as-is if possible. If it
          returns a callble, the iterator returned by that callable is passed
          in here.
  
          Each element in `information` is a named tuple with two entries:
  
          * `requirement` specifies a requirement contributing to the current
            candidate list.
          * `parent` specifies the candidate that provides (dependend on) the
            requirement, or `None` to indicate a root requirement.
  
          The preference could depend on a various of issues, including (not
          necessarily in this order):
  
          * Is this package pinned in the current resolution result?
          * How relaxed is the requirement? Stricter ones should probably be
            worked on first? (I don't know, actually.)
          * How many possibilities are there to satisfy this requirement? Those
            with few left should likely be worked on first, I guess?
          * Are there any known conflicts for this requirement? We should
            probably work on those with the most known conflicts.
  
          A sortable value should be returned (this will be used as the `key`
          parameter of the built-in sorting function). The smaller the value is,
          the more preferred this requirement is (i.e. the sorting function
          is called with `reverse=False`).
          """
          raise NotImplementedError
function_tokens: def get_preference ( self , resolution , candidates , information ) : raise NotImplementedError