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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 delete_field(field_uri):
 """ Helper function to request deletion of a field. This is necessary when you want to overwrite values instead of appending. <t:DeleteItemField> <t:FieldURI FieldURI="calendar:Resources"/> </t:DeleteItemField> """


  root = T.DeleteItemField(
    T.FieldURI(FieldURI=field_uri)
  )

  return root