docs: def pkg_manager_view(
              self, package_names, stream=None, explicit=False, **kw):
          """
          Returns the manifest JSON for the Python package name.  Default
          npm implementation calls for package.json.
  
          If this class is initiated using standard procedures, this will
          mimic the functionality of ``npm view`` but mostly for showing
          the dependencies.  This is done as a default action.
  
          Arguments:
  
          package_names
              The names of the python packages with their requirements to
              source the package.json from.
          stream
              If specified, the generated package.json will be written to
              there.
          explicit
              If True, the package names specified are the explicit list
              to search for - no dependency resolution will then be done.
  
          Returns the manifest json as a dict.
          """
  
          # For looking up the pkg_name to dist converter for explicit
          to_dists = {
              False: find_packages_requirements_dists,
              True: pkg_names_to_dists,
          }
  
          # assuming string, and assume whitespaces are invalid.
          pkg_names, malformed = convert_package_names(package_names)
          if malformed:
              msg = 'malformed package name(s) specified: %s' % ', '.join(
                  malformed)
              raise ValueError(msg)
  
          if len(pkg_names) == 1:
              logger.info(
                  "generating a flattened '%s' for '%s'",
                  self.pkgdef_filename, pkg_names[0],
              )
          else:
              logger.info(
                  "generating a flattened '%s' for packages {%s}",
                  self.pkgdef_filename, ', '.join(pkg_names),
              )
  
          # remember the filename is in the context of the distribution,
          # not the filesystem.
          dists = to_dists[explicit](pkg_names)
          pkgdef_json = flatten_dist_egginfo_json(
              dists, filename=self.pkgdef_filename,
              dep_keys=self.dep_keys,
          )
  
          if pkgdef_json.get(
                  self.pkg_name_field, NotImplemented) is NotImplemented:
              # use the last item.
              pkg_name = Requirement.parse(pkg_names[-1]).project_name
              pkgdef_json[self.pkg_name_field] = pkg_name
  
          if stream:
              self.dump(pkgdef_json, stream)
              stream.write('\n')
  
          return pkgdef_json