code: def close_position(p, position, tdate):
      r"""Close the position and remove it from the portfolio.
  
      Parameters
      ----------
      p : alphapy.Portfolio
          Portfolio holding the position.
      position : alphapy.Position
          Position to close.
      tdate : datetime
          The date for pricing the closed position.
  
      Returns
      -------
      p : alphapy.Portfolio
          Portfolio with the removed position.
  
      """
      pq = position.quantity
      # if necessary, put on an offsetting trade
      if pq != 0:
          tradesize = -pq
          position.date = tdate
          pdata = position.pdata
          cp = pdata.loc[tdate]["close"]
          newtrade = Trade(position.name, tradesize, cp, tdate)
          p = update_portfolio(p, position, newtrade)
          position.quantity = 0
      position.status = "closed"
      p = remove_position(p, position.name)
      return p
  
imports: from alphapy.frame import Frame
  from alphapy.frame import frame_name
  from alphapy.frame import read_frame
  from alphapy.frame import write_frame
  from alphapy.globals import MULTIPLIERS, SSEP
  from alphapy.globals import Orders
  from alphapy.space import Space
  import logging
  import math
  import numpy
  from pandas import DataFrame
  from pandas import date_range
  from pandas import Series
label_desc: Use image node_id 6 for calling a global function with example usage: close_position(p, position, tdate) and returns: p