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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 real_python3(python, version_dict):
 """ Determine the path of the real python executable, which is then used for venv creation. This is necessary, because an active virtualenv environment will cause venv creation to malfunction. By getting the path of the real executable, this issue is bypassed. The provided `python` path may be either: - A real python executable - A virtual python executable (with venv) - A virtual python executable (with virtualenv) If the virtual environment was created with virtualenv, the `sys` module will have a `real_prefix` attribute, which points to the directory where the real python files are installed. If `real_prefix` is not present, the environment was not created with virtualenv, and the python executable is safe to use. The `version_dict` is used for attempting to derive the real executable path. This is necessary when the name of the virtual python executable does not exist in the Python installation's directory. For example, if the `basepython` is explicitly set to `python`, tox will use this name instead of attempting `pythonX.Y`. In many cases, Python 3 installations do not contain an executable named `python`, so we attempt to derive this from the version info. e.g., `python3.6.5`, `python3.6`, then `python3`. """

    args = [python, '-c', 'import sys; print(sys.real_prefix)']

    # get python prefix
    try:
        output = subprocess.check_output(args, stderr=subprocess.STDOUT)
        prefix = output.decode('UTF-8').strip()
    except subprocess.CalledProcessError:
        # process fails, implies *not* in active virtualenv
        return python

    # determine absolute binary path
    if os.name == 'nt':  # pragma: no cover
        paths = [os.path.join(prefix, os.path.basename(python))]
    else:
        paths = [os.path.join(prefix, 'bin', python) for python in [
            os.path.basename(python),
            'python%(major)d.%(minor)d.%(micro)d' % version_dict,
            'python%(major)d.%(minor)d' % version_dict,
            'python%(major)d' % version_dict,
            'python',
        ]]

    for path in paths:
        if os.path.isfile(path):
            break
    else:
        path = None

    # the executable path must exist
    assert path, '\n- '.join(['Could not find interpreter. Attempted:'] + paths)
    v1 = subprocess.check_output([python, '--version'])
    v2 = subprocess.check_output([path, '--version'])
    assert v1 == v2, 'Expected versions to match (%s != %s).' % (v1, v2)

    return path