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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 get_memfree(memory, parallel):
 """Computes the memory required for the memfree field."""

  number = int(memory.rstrip(string.ascii_letters))
  memtype = memory.lstrip(string.digits)
  if not memtype:
    memtype = "G"
  return "%d%s" % (number*parallel, memtype)