prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Breaking change in sync httpx refactor from #1403
  elastic/apm-agent-python#1403 refactored a lot of the httpx code. However it seems that the sync version of the instrumentation still calls `self._set_disttracing_headers` which was removed in the same PR, causing any form of sync httpx instrumentation to crash.
  
  **Environment (please complete the following information)**
  - Agent version: 6.7.1
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `elasticapm/instrumentation/packages/httpx/sync/httpcore.py`
  Content:
  ```
  1 #  BSD 3-Clause License
  2 #
  3 #  Copyright (c) 2021, Elasticsearch BV
  4 #  All rights reserved.
  5 #
  6 #  Redistribution and use in source and binary forms, with or without
  7 #  modification, are permitted provided that the following conditions are met:
  8 #
  9 #  * Redistributions of source code must retain the above copyright notice, this
  10 #    list of conditions and the following disclaimer.
  11 #
  12 #  * Redistributions in binary form must reproduce the above copyright notice,
  13 #    this list of conditions and the following disclaimer in the documentation
  14 #    and/or other materials provided with the distribution.
  15 #
  16 #  * Neither the name of the copyright holder nor the names of its
  17 #    contributors may be used to endorse or promote products derived from
  18 #    this software without specific prior written permission.
  19 #
  20 #  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  21 #  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22 #  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  23 #  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  24 #  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25 #  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  26 #  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  27 #  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  28 #  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29 #  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30 
  31 from elasticapm.instrumentation.packages.base import AbstractInstrumentedModule
  32 from elasticapm.instrumentation.packages.httpx import utils
  33 from elasticapm.traces import DroppedSpan, capture_span, execution_context
  34 from elasticapm.utils import default_ports
  35 from elasticapm.utils.disttracing import TracingOptions
  36 
  37 
  38 class HTTPCoreInstrumentation(AbstractInstrumentedModule):
  39     name = "httpcore"
  40 
  41     instrument_list = [
  42         ("httpcore._sync.connection", "SyncHTTPConnection.request"),  # < httpcore 0.13
  43         ("httpcore._sync.connection", "SyncHTTPConnection.handle_request"),  # >= httpcore 0.13
  44         ("httpcore._sync.connection", "HTTPConnection.handle_request"),  # httpcore >= 0.14 (hopefully...)
  45     ]
  46 
  47     def call(self, module, method, wrapped, instance, args, kwargs):
  48         url, method, headers = utils.get_request_data(args, kwargs)
  49         scheme, host, port, target = url
  50         if port != default_ports.get(scheme):
  51             host += ":" + str(port)
  52 
  53         signature = "%s %s" % (method.upper(), host)
  54 
  55         url = "%s://%s%s" % (scheme, host, target)
  56 
  57         transaction = execution_context.get_transaction()
  58 
  59         with capture_span(
  60             signature,
  61             span_type="external",
  62             span_subtype="http",
  63             extra={"http": {"url": url}},
  64             leaf=True,
  65         ) as span:
  66             # if httpcore has been called in a leaf span, this span might be a DroppedSpan.
  67             leaf_span = span
  68             while isinstance(leaf_span, DroppedSpan):
  69                 leaf_span = leaf_span.parent
  70 
  71             if headers is not None:
  72                 # It's possible that there are only dropped spans, e.g. if we started dropping spans.
  73                 # In this case, the transaction.id is used
  74                 parent_id = leaf_span.id if leaf_span else transaction.id
  75                 trace_parent = transaction.trace_parent.copy_from(
  76                     span_id=parent_id, trace_options=TracingOptions(recorded=True)
  77                 )
  78                 utils.set_disttracing_headers(headers, trace_parent, transaction)
  79                 if leaf_span:
  80                     leaf_span.dist_tracing_propagated = True
  81             response = wrapped(*args, **kwargs)
  82             status_code = utils.get_status(response)
  83             if status_code:
  84                 if span.context:
  85                     span.context["http"]["status_code"] = status_code
  86                 span.set_success() if status_code < 400 else span.set_failure()
  87             return response
  88 
  89     def mutate_unsampled_call_args(self, module, method, wrapped, instance, args, kwargs, transaction):
  90         # since we don't have a span, we set the span id to the transaction id
  91         trace_parent = transaction.trace_parent.copy_from(
  92             span_id=transaction.id, trace_options=TracingOptions(recorded=False)
  93         )
  94         if "headers" in kwargs:
  95             headers = kwargs["headers"]
  96             if headers is None:
  97                 headers = []
  98                 kwargs["headers"] = headers
  99             self._set_disttracing_headers(headers, trace_parent, transaction)
  100         return args, kwargs
  101
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/elasticapm/instrumentation/packages/httpx/sync/httpcore.py b/elasticapm/instrumentation/packages/httpx/sync/httpcore.py
  --- a/elasticapm/instrumentation/packages/httpx/sync/httpcore.py
  +++ b/elasticapm/instrumentation/packages/httpx/sync/httpcore.py
  @@ -91,10 +91,6 @@
           trace_parent = transaction.trace_parent.copy_from(
               span_id=transaction.id, trace_options=TracingOptions(recorded=False)
           )
  -        if "headers" in kwargs:
  -            headers = kwargs["headers"]
  -            if headers is None:
  -                headers = []
  -                kwargs["headers"] = headers
  -            self._set_disttracing_headers(headers, trace_parent, transaction)
  +        headers = utils.get_request_data(args, kwargs)[2]
  +        utils.set_disttracing_headers(headers, trace_parent, transaction)
           return args, kwargs
  
verification_info: {"golden_diff": "diff --git a/elasticapm/instrumentation/packages/httpx/sync/httpcore.py b/elasticapm/instrumentation/packages/httpx/sync/httpcore.py\n--- a/elasticapm/instrumentation/packages/httpx/sync/httpcore.py\n+++ b/elasticapm/instrumentation/packages/httpx/sync/httpcore.py\n@@ -91,10 +91,6 @@\n         trace_parent = transaction.trace_parent.copy_from(\n             span_id=transaction.id, trace_options=TracingOptions(recorded=False)\n         )\n-        if \"headers\" in kwargs:\n-            headers = kwargs[\"headers\"]\n-            if headers is None:\n-                headers = []\n-                kwargs[\"headers\"] = headers\n-            self._set_disttracing_headers(headers, trace_parent, transaction)\n+        headers = utils.get_request_data(args, kwargs)[2]\n+        utils.set_disttracing_headers(headers, trace_parent, transaction)\n         return args, kwargs\n", "issue": "Breaking change in sync httpx refactor from #1403\nelastic/apm-agent-python#1403 refactored a lot of the httpx code. However it seems that the sync version of the instrumentation still calls `self._set_disttracing_headers` which was removed in the same PR, causing any form of sync httpx instrumentation to crash.\r\n\r\n**Environment (please complete the following information)**\r\n- Agent version: 6.7.1\n", "before_files": [{"content": "#  BSD 3-Clause License\n#\n#  Copyright (c) 2021, Elasticsearch BV\n#  All rights reserved.\n#\n#  Redistribution and use in source and binary forms, with or without\n#  modification, are permitted provided that the following conditions are met:\n#\n#  * Redistributions of source code must retain the above copyright notice, this\n#    list of conditions and the following disclaimer.\n#\n#  * Redistributions in binary form must reproduce the above copyright notice,\n#    this list of conditions and the following disclaimer in the documentation\n#    and/or other materials provided with the distribution.\n#\n#  * Neither the name of the copyright holder nor the names of its\n#    contributors may be used to endorse or promote products derived from\n#    this software without specific prior written permission.\n#\n#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS \"AS IS\"\n#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\n#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE\n#  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE\n#  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\n#  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR\n#  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER\n#  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,\n#  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n#  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n\nfrom elasticapm.instrumentation.packages.base import AbstractInstrumentedModule\nfrom elasticapm.instrumentation.packages.httpx import utils\nfrom elasticapm.traces import DroppedSpan, capture_span, execution_context\nfrom elasticapm.utils import default_ports\nfrom elasticapm.utils.disttracing import TracingOptions\n\n\nclass HTTPCoreInstrumentation(AbstractInstrumentedModule):\n    name = \"httpcore\"\n\n    instrument_list = [\n        (\"httpcore._sync.connection\", \"SyncHTTPConnection.request\"),  # < httpcore 0.13\n        (\"httpcore._sync.connection\", \"SyncHTTPConnection.handle_request\"),  # >= httpcore 0.13\n        (\"httpcore._sync.connection\", \"HTTPConnection.handle_request\"),  # httpcore >= 0.14 (hopefully...)\n    ]\n\n    def call(self, module, method, wrapped, instance, args, kwargs):\n        url, method, headers = utils.get_request_data(args, kwargs)\n        scheme, host, port, target = url\n        if port != default_ports.get(scheme):\n            host += \":\" + str(port)\n\n        signature = \"%s %s\" % (method.upper(), host)\n\n        url = \"%s://%s%s\" % (scheme, host, target)\n\n        transaction = execution_context.get_transaction()\n\n        with capture_span(\n            signature,\n            span_type=\"external\",\n            span_subtype=\"http\",\n            extra={\"http\": {\"url\": url}},\n            leaf=True,\n        ) as span:\n            # if httpcore has been called in a leaf span, this span might be a DroppedSpan.\n            leaf_span = span\n            while isinstance(leaf_span, DroppedSpan):\n                leaf_span = leaf_span.parent\n\n            if headers is not None:\n                # It's possible that there are only dropped spans, e.g. if we started dropping spans.\n                # In this case, the transaction.id is used\n                parent_id = leaf_span.id if leaf_span else transaction.id\n                trace_parent = transaction.trace_parent.copy_from(\n                    span_id=parent_id, trace_options=TracingOptions(recorded=True)\n                )\n                utils.set_disttracing_headers(headers, trace_parent, transaction)\n                if leaf_span:\n                    leaf_span.dist_tracing_propagated = True\n            response = wrapped(*args, **kwargs)\n            status_code = utils.get_status(response)\n            if status_code:\n                if span.context:\n                    span.context[\"http\"][\"status_code\"] = status_code\n                span.set_success() if status_code < 400 else span.set_failure()\n            return response\n\n    def mutate_unsampled_call_args(self, module, method, wrapped, instance, args, kwargs, transaction):\n        # since we don't have a span, we set the span id to the transaction id\n        trace_parent = transaction.trace_parent.copy_from(\n            span_id=transaction.id, trace_options=TracingOptions(recorded=False)\n        )\n        if \"headers\" in kwargs:\n            headers = kwargs[\"headers\"]\n            if headers is None:\n                headers = []\n                kwargs[\"headers\"] = headers\n            self._set_disttracing_headers(headers, trace_parent, transaction)\n        return args, kwargs\n", "path": "elasticapm/instrumentation/packages/httpx/sync/httpcore.py"}], "after_files": [{"content": "#  BSD 3-Clause License\n#\n#  Copyright (c) 2021, Elasticsearch BV\n#  All rights reserved.\n#\n#  Redistribution and use in source and binary forms, with or without\n#  modification, are permitted provided that the following conditions are met:\n#\n#  * Redistributions of source code must retain the above copyright notice, this\n#    list of conditions and the following disclaimer.\n#\n#  * Redistributions in binary form must reproduce the above copyright notice,\n#    this list of conditions and the following disclaimer in the documentation\n#    and/or other materials provided with the distribution.\n#\n#  * Neither the name of the copyright holder nor the names of its\n#    contributors may be used to endorse or promote products derived from\n#    this software without specific prior written permission.\n#\n#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS \"AS IS\"\n#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\n#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE\n#  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE\n#  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\n#  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR\n#  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER\n#  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,\n#  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n#  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\n\nfrom elasticapm.instrumentation.packages.base import AbstractInstrumentedModule\nfrom elasticapm.instrumentation.packages.httpx import utils\nfrom elasticapm.traces import DroppedSpan, capture_span, execution_context\nfrom elasticapm.utils import default_ports\nfrom elasticapm.utils.disttracing import TracingOptions\n\n\nclass HTTPCoreInstrumentation(AbstractInstrumentedModule):\n    name = \"httpcore\"\n\n    instrument_list = [\n        (\"httpcore._sync.connection\", \"SyncHTTPConnection.request\"),  # < httpcore 0.13\n        (\"httpcore._sync.connection\", \"SyncHTTPConnection.handle_request\"),  # >= httpcore 0.13\n        (\"httpcore._sync.connection\", \"HTTPConnection.handle_request\"),  # httpcore >= 0.14 (hopefully...)\n    ]\n\n    def call(self, module, method, wrapped, instance, args, kwargs):\n        url, method, headers = utils.get_request_data(args, kwargs)\n        scheme, host, port, target = url\n        if port != default_ports.get(scheme):\n            host += \":\" + str(port)\n\n        signature = \"%s %s\" % (method.upper(), host)\n\n        url = \"%s://%s%s\" % (scheme, host, target)\n\n        transaction = execution_context.get_transaction()\n\n        with capture_span(\n            signature,\n            span_type=\"external\",\n            span_subtype=\"http\",\n            extra={\"http\": {\"url\": url}},\n            leaf=True,\n        ) as span:\n            # if httpcore has been called in a leaf span, this span might be a DroppedSpan.\n            leaf_span = span\n            while isinstance(leaf_span, DroppedSpan):\n                leaf_span = leaf_span.parent\n\n            if headers is not None:\n                # It's possible that there are only dropped spans, e.g. if we started dropping spans.\n                # In this case, the transaction.id is used\n                parent_id = leaf_span.id if leaf_span else transaction.id\n                trace_parent = transaction.trace_parent.copy_from(\n                    span_id=parent_id, trace_options=TracingOptions(recorded=True)\n                )\n                utils.set_disttracing_headers(headers, trace_parent, transaction)\n                if leaf_span:\n                    leaf_span.dist_tracing_propagated = True\n            response = wrapped(*args, **kwargs)\n            status_code = utils.get_status(response)\n            if status_code:\n                if span.context:\n                    span.context[\"http\"][\"status_code\"] = status_code\n                span.set_success() if status_code < 400 else span.set_failure()\n            return response\n\n    def mutate_unsampled_call_args(self, module, method, wrapped, instance, args, kwargs, transaction):\n        # since we don't have a span, we set the span id to the transaction id\n        trace_parent = transaction.trace_parent.copy_from(\n            span_id=transaction.id, trace_options=TracingOptions(recorded=False)\n        )\n        headers = utils.get_request_data(args, kwargs)[2]\n        utils.set_disttracing_headers(headers, trace_parent, transaction)\n        return args, kwargs\n", "path": "elasticapm/instrumentation/packages/httpx/sync/httpcore.py"}]}