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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 owner(path):
 """Returns a tuple containing the username & groupname owning the path. :param str path: the string path to retrieve the ownership :return tuple(str, str):
 A (username, groupname) tuple containing the name of the user and group owning the path. :raises OSError: if the specified path does not exist """

    stat = os.stat(path)
    username = pwd.getpwuid(stat.st_uid)[0]
    groupname = grp.getgrgid(stat.st_gid)[0]
    return username, groupname