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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 get_pkg_names(pkgs):
 """Get PyPI package names from a list of imports. Args: pkgs (List[str]):
 List of import names. Returns: List[str]: The corresponding PyPI package names. """

    result = set()
    with open(join("mapping"), "r") as f:
        data = dict(x.strip().split(":") for x in f)
    for pkg in pkgs:
        # Look up the mapped requirement. If a mapping isn't found,
        # simply use the package name.
        result.add(data.get(pkg, pkg))
    # Return a sorted list for backward compatibility.
    return sorted(result, key=lambda s: s.lower())