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https://issues.apache.org/jira/browse/ARROW-15765?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17496876#comment-17496876
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Weston Pace commented on ARROW-15765:
-------------------------------------

Perhaps I am missing some key piece but don't all arrays (Int32Array, 
Int64Array, etc.) extend Array which already has a type field?

{noformat}
cdef class Array(_PandasConvertible):
    cdef:
        shared_ptr[CArray] sp_array
        CArray* ap

    cdef readonly:
        DataType type
{noformat}

So couldn't you do `array1.type`?

{noformat}
>>> x = pa.array([1, 2, 3])
>>> x.type
DataType(int64)
{noformat}

> [Python] Extracting Type information from Python Objects
> --------------------------------------------------------
>
>                 Key: ARROW-15765
>                 URL: https://issues.apache.org/jira/browse/ARROW-15765
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++, Python
>            Reporter: Vibhatha Lakmal Abeykoon
>            Assignee: Vibhatha Lakmal Abeykoon
>            Priority: Major
>
> When creating user defined functions or similar exercises where we want to 
> extract the Arrow data types from the type hints, the existing Python API 
> have some limitations. 
> An example case is as follows;
> {code:java}
> def function(array1: pa.Int64Array, arrya2: pa.Int64Array) -> pa.Int64Array:
>     return pc.call_function("add", [array1, array2])
>   {code}
> We want to extract the fact that array1 is an `pa.Array` of `pa.Int32Type`. 
> At the moment there doesn't exist a straightforward manner to get this done. 
> So the idea is to expose this feature to Python. 



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