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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_a_system_python(line):
 """Find a Python installation from a given line. This tries to parse the line in various of ways: * Looks like an absolute path? Use it directly. * Looks like a py.exe call? Use py.exe to get the executable. * Starts with "py" something? Looks like a python command. Try to find it in PATH, and use it directly. * Search for "python" and "pythonX.Y" executables in PATH to find a match. * Nothing fits, return None. """


    from .vendor.pythonfinder import Finder
    finder = Finder(system=False, global_search=True)
    if not line:
        return next(iter(finder.find_all_python_versions()), None)
    # Use the windows finder executable
    if (line.startswith("py ") or line.startswith("py.exe ")) and os.name == "nt":
        line = line.split(" ", 1)[1].lstrip("-")
    python_entry = find_python(finder, line)
    return python_entry