code: def create_virtualenv(self):
          
          if check_command('virtualenv'):
              ve_dir = os.path.join(self._ve_dir, self._project_name)
              if os.path.exists(ve_dir):
                  if self._force:
                      logging.warn('Removing existing virtualenv')
                      shutil.rmtree(ve_dir)
                  else:
                      logging.warn('Found existing virtualenv; not creating (use --force to overwrite)')
                      return
              logging.info('Creating virtualenv')
              p = subprocess.Popen('virtualenv --no-site-packages {0} > /dev/null'.format(ve_dir), shell=True)
              os.waitpid(p.pid, 0)
              # install modules
              for m in self._modules:
                  self.log.info('Installing module {0}'.format(m))
                  p = subprocess.Popen('{0} install {1} > /dev/null'.format(os.path.join(self._ve_dir, \
                  self._project_name) + os.sep + 'bin' + os.sep + 'pip', m), shell=True)
                  os.waitpid(p.pid, 0)
docs: Creates the virtualenv for the project