Correct and Incorrect Way to Use ConcurrentDictionary

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let myCache = new System.Collections.Concurrent.ConcurrentDictionary<string,_>()
let createType() = "some method"

val myCache : System.Collections.Concurrent.ConcurrentDictionary<string,string>

Full name: Script.myCache

namespace System

namespace System.Collections

namespace System.Collections.Concurrent

Multiple items
type ConcurrentDictionary<'TKey,'TValue> =
  new : unit -> ConcurrentDictionary<'TKey, 'TValue> + 6 overloads
  member AddOrUpdate : key:'TKey * addValueFactory:Func<'TKey, 'TValue> * updateValueFactory:Func<'TKey, 'TValue, 'TValue> -> 'TValue + 1 overload
  member Clear : unit -> unit
  member ContainsKey : key:'TKey -> bool
  member Count : int
  member GetEnumerator : unit -> IEnumerator<KeyValuePair<'TKey, 'TValue>>
  member GetOrAdd : key:'TKey * valueFactory:Func<'TKey, 'TValue> -> 'TValue + 1 overload
  member IsEmpty : bool
  member Item : 'TKey -> 'TValue with get, set
  member Keys : ICollection<'TKey>
  ...

Full name: System.Collections.Concurrent.ConcurrentDictionary<_,_>

--------------------
System.Collections.Concurrent.ConcurrentDictionary() : unit
System.Collections.Concurrent.ConcurrentDictionary(collection: System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<'TKey,'TValue>>) : unit
System.Collections.Concurrent.ConcurrentDictionary(comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit
System.Collections.Concurrent.ConcurrentDictionary(concurrencyLevel: int, capacity: int) : unit
System.Collections.Concurrent.ConcurrentDictionary(collection: System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<'TKey,'TValue>>, comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit
System.Collections.Concurrent.ConcurrentDictionary(concurrencyLevel: int, collection: System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<'TKey,'TValue>>, comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit
System.Collections.Concurrent.ConcurrentDictionary(concurrencyLevel: int, capacity: int, comparer: System.Collections.Generic.IEqualityComparer<'TKey>) : unit

Multiple items
val string : value:'T -> string

Full name: Microsoft.FSharp.Core.Operators.string

--------------------
type string = System.String

Full name: Microsoft.FSharp.Core.string

val createType : unit -> string

Full name: Script.createType