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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 mk_id(field):
 """Builds an identifier from a field. """

  name = field.type_id
  if name == "string":
    return "%s" % ("char")
  elif name == "array" and field.size:
    if field.options['fill'].value not in CONSTRUCT_CODE:
      return "%s" % convert(field.options['fill'].value)
    else:
      return "%s" % field.options['fill'].value
  elif name == "array":
    return "%s" % convert(field.options['fill'].value)
  elif name not in CONSTRUCT_CODE:
    return convert(name)
  else:
    return name