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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def xpacheck():
 	"""Check if xpa is running"""

	import os
	f=os.popen('xpaaccess ds9')
	l=f.readline()
	f.close()
	if l.strip()!='yes':
   		logger.debug("\t Can't get ds9 access, xpaccess said: %s" % ( l.strip()))
		return (False)
	return(True)