code: def create(self, python=None, system_site=False, always_copy=False):
          
          command = 'virtualenv'
          if python:
  
              command = '{0} --python={1}'.format(command, python)
  
          if system_site:
  
              command = '{0} --system-site-packages'.format(command)
  
          if always_copy:
  
              command = '{0} --always-copy'.format(command)
  
          command = '{0} {1}'.format(command, self.path)
          self._execute(command)
docs: Create a new virtual environment.
  
          Args:
              python (str): The name or path of a python interpreter to use while
                  creating the virtual environment.
              system_site (bool): Whether or not use use the system site packages
                  within the virtual environment. Default is False.
              always_copy (bool): Whether or not to force copying instead of
                  symlinking in the virtual environment. Default is False.