400, 'mapper_parsing_exception', 'No type specified for field [file]'

I am using the following code to create an index. Don't understand what is required to fix the error.

es.indices.create(
index= "prestotest",
body= {
"mappings": {
"properties": {
"file" : {
"properties ": {
"url": {
"type": "keyword",
"index": False
}
}
}
}
},
"settings": {
"analysis": {
"analyzer": {
"std_english": {
"type": "standard",
"stopwords": "english"
}
}
}
}
}
)Preformatted text