code: def download_and_compile_igraph(self):
          
          print("We will now try to download and compile the C core from scratch.")
          print("Version number of the C core: %s" % self.c_core_versions[0])
          if len(self.c_core_versions) > 1:
              print("We will also try: %s" % ", ".join(self.c_core_versions[1:]))
          print("")
  
          igraph_builder = IgraphCCoreBuilder(self.c_core_versions, self.c_core_url,
                  show_progress_bar=self.show_progress_bar)
          if not igraph_builder.run():
              print("Could not download and compile the C core of igraph.")
              print("")
              return False
          else:
              return True
docs: Downloads and compiles the C core of igraph.