gradio

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import ast
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import os
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import sys
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import tokenize
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import types
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from inspect import CO_COROUTINE
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from gradio.wasm_utils import app_id_context
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# BSD 3-Clause License
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#
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# - Copyright (c) 2008-Present, IPython Development Team
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# - Copyright (c) 2001-2007, Fernando Perez <fernando.perez@colorado.edu>
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# - Copyright (c) 2001, Janko Hauser <jhauser@zscout.de>
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# - Copyright (c) 2001, Nathaniel Gray <n8gray@caltech.edu>
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#
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are met:
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#
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# * Redistributions of source code must retain the above copyright notice, this
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#   list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above copyright notice,
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#   this list of conditions and the following disclaimer in the documentation
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#   and/or other materials provided with the distribution.
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# * Neither the name of the copyright holder nor the names of its
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#   contributors may be used to endorse or promote products derived from
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#   this software without specific prior written permission.
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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# Code modified from IPython (BSD license)
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# Source: https://github.com/ipython/ipython/blob/master/IPython/utils/syspathcontext.py#L42
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class modified_sys_path:  # noqa: N801
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    """A context for prepending a directory to sys.path for a second."""
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    def __init__(self, script_path: str):
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        self._script_path = script_path
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        self._added_path = False
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    def __enter__(self):
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        if self._script_path not in sys.path:
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            sys.path.insert(0, self._script_path)
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            self._added_path = True
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    def __exit__(self, type, value, traceback):
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        if self._added_path:
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            try:
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                sys.path.remove(self._script_path)
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            except ValueError:
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                # It's already removed.
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                pass
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        # Returning False causes any exceptions to be re-raised.
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        return False
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# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022)
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# Copyright (c) Yuichiro Tachibana (2023)
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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#     http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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def _new_module(name: str) -> types.ModuleType:
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    """Create a new module with the given name."""
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    return types.ModuleType(name)
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def set_home_dir(home_dir: str) -> None:
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    os.environ["HOME"] = home_dir
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    os.chdir(home_dir)
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async def _run_script(app_id: str, home_dir: str, script_path: str) -> None:
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    # This function is based on the following code from Streamlit:
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    # https://github.com/streamlit/streamlit/blob/1.24.0/lib/streamlit/runtime/scriptrunner/script_runner.py#L519-L554
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    # with modifications to support top-level await.
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    set_home_dir(home_dir)
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    with tokenize.open(script_path) as f:
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        filebody = f.read()
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    await _run_code(app_id, home_dir, filebody, script_path)
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async def _run_code(
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        app_id: str,
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        home_dir: str,
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        filebody: str,
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        script_path: str = '<string>'  # This default value follows the convention. Ref: https://docs.python.org/3/library/functions.html#compile
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    ) -> None:
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    set_home_dir(home_dir)
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    # NOTE: In Streamlit, the bytecode caching mechanism has been introduced.
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    # However, we skipped it here for simplicity and because Gradio doesn't need to rerun the script so frequently,
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    # while we may do it in the future.
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    bytecode = compile(  # type: ignore
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        filebody,
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        # Pass in the file path so it can show up in exceptions.
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        script_path,
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        # We're compiling entire blocks of Python, so we need "exec"
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        # mode (as opposed to "eval" or "single").
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        mode="exec",
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        # Don't inherit any flags or "future" statements.
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        flags=ast.PyCF_ALLOW_TOP_LEVEL_AWAIT, # Allow top-level await. Ref: https://github.com/whitphx/streamlit/commit/277dc580efb315a3e9296c9a0078c602a0904384
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        dont_inherit=1,
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        # Use the default optimization options.
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        optimize=-1,
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    )
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    module = _new_module("__main__")
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    # Install the fake module as the __main__ module. This allows
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    # the pickle module to work inside the user's code, since it now
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    # can know the module where the pickled objects stem from.
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    # IMPORTANT: This means we can't use "if __name__ == '__main__'" in
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    # our code, as it will point to the wrong module!!!
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    sys.modules["__main__"] = module
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    # Add special variables to the module's globals dict.
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    module.__dict__["__file__"] = script_path
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    with modified_sys_path(script_path), modified_sys_path(home_dir), app_id_context(app_id):
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        # Allow top-level await. Ref: https://github.com/whitphx/streamlit/commit/277dc580efb315a3e9296c9a0078c602a0904384
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        if bytecode.co_flags & CO_COROUTINE:
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            # The source code includes top-level awaits, so the compiled code object is a coroutine.
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            await eval(bytecode, module.__dict__)
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        else:
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            exec(bytecode, module.__dict__)
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