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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find_site_python(module_name, paths=None):
 """Find the rez native python package that contains the given module. This function is used by python 'native' rez installers to find the native rez python package that represents the python installation that this module is installed into. Note: This function is dependent on the behavior found in the python '_native' package found in the 'rez-recipes' repository. Specifically, it expects to find a python package with a '_site_paths' list attribute listing the site directories associated with the python installation. Args: module_name (str):
 Target python module. paths (list of str, optional):
 paths to search for packages, defaults to `config.packages_path`. Returns: `Package`: Native python package containing the named module. """

    from rez.packages_ import iter_packages
    import subprocess
    import ast
    import os

    py_cmd = 'import {x}; print {x}.__path__'.format(x=module_name)

    p = popen(["python", "-c", py_cmd], stdout=subprocess.PIPE,
               stderr=subprocess.PIPE)
    out, err = p.communicate()

    if p.returncode:
        raise InvalidPackageError(
            "Failed to find installed python module '%s':\n%s"
            % (module_name, err))

    module_paths = ast.literal_eval(out.strip())

    def issubdir(path, parent_path):
        return path.startswith(parent_path + os.sep)

    for package in iter_packages("python", paths=paths):
        if not hasattr(package, "_site_paths"):
            continue

        contained = True

        for module_path in module_paths:
            if not any(issubdir(module_path, x) for x in package._site_paths):
                contained = False

        if contained:
            return package

    raise InvalidPackageError(
        "Failed to find python installation containing the module '%s'. Has "
        "python been installed as a rez package?" % module_name)