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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_packages(name, pkg_dir):
 """Locate pre-built packages in the _packages directory"""

    for c in (FileSystemPackageBuilder, ZipPackageBuilder, ExcelPackageBuilder):

        package_path, cache_path = c.make_package_path(pkg_dir, name)

        if package_path.exists():

            yield c.type_code, package_path, cache_path