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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 create_alias(target_path, alias_path):
 """Creates an alias at 'alias_path' pointing to the file 'target_path'. On Unix, this is implemented via symlink. On Windows, this is done by creating a Windows shortcut file. Args: target_path: Destination path that the alias should point to. alias_path: Path at which to create the new alias. """

    if platform.system() == 'Windows' and not alias_path.endswith('.lnk'):
        alias_path += '.lnk'
    if os.path.lexists(alias_path):
        os.remove(alias_path)
    if platform.system() == 'Windows':
        from win32com import client
        shell = client.Dispatch('WScript.Shell')
        shortcut = shell.CreateShortCut(alias_path)
        shortcut.Targetpath = target_path
        shortcut.save()
    else:
        os.symlink(target_path, alias_path)