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### Description I used [get_body_part_by_filter](https://github.com/kamailio/kamailio/blob/f073f72af6a507e8113e06dc07ad161e3f...) to extract a body part from a `multipart/mixed` message. It works as expected but for every body part it compares and do not match (until finding the one that matches the filter) it shows error log messages like:

`ERROR: <core> [core/parser/parse_body.c:513]: part_multipart_headers_cmp(): part_multipart_headers_cmp. error. "-2". "MIME types mismatch".`

The comparison of body parts shouldn´t be logged as errors, since they are not.

<!-- Explain what you did, what you expected to happen, and what actually happened. -->

### Expected behavior

No error logs.

#### Actual observed behavior

Error log messages.

#### Log Messages

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``` ERROR: <core> [core/parser/parse_body.c:513]: part_multipart_headers_cmp(): part_multipart_headers_cmp. error. "-2". "MIME types mismatch". ``` ### Possible Solutions

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### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` 5.1 ```

* **Operating System**:

<!-- Details about the operating system, the type: Linux (e.g.,: Debian 8.4, Ubuntu 16.04, CentOS 7.1, ...), MacOS, xBSD, Solaris, ...; Kernel details (output of `uname -a`) -->

``` CentOS 7 ```