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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_size(field):
 """Builds an identifier for a container type. """

  name = field.type_id
  if name == "string" and field.options.get('size', None):
    return "%s[%d];" % (field.identifier, field.options.get('size').value)
  elif name == "string":
    return "%s[0];" % field.identifier
  elif name == "array" and field.options.get('size', None):
    return "%s[%d];" % (field.identifier, field.options.get('size').value)
  elif name == "array":
    return "%s[0];" % field.identifier
  else:
    return '%s;' % field.identifier