code: def backup(filename):
      
      tmp_file = "/tmp/%s" % filename
      # We dump to /tmp because user "postgres" can't write to other user folders
      # We cd to / because user "postgres" might not have read permissions
      # elsewhere.
      with cd("/"):
          postgres("pg_dump -Fc %s > %s" % (env.proj_name, tmp_file))
      run("cp %s ." % tmp_file)
      sudo("rm -f %s" % tmp_file)
docs: Backs up the project database.