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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_log(log_file, uid):
 """ Create log file and set necessary permissions. Args: log_file (str):
 Path to the log file. uid (int):
 User ID - will be used for chown. """

    if not os.path.exists(log_file):  # create new log file
        dir_name = os.path.dirname(log_file)
        if not os.path.exists(dir_name):
            os.makedirs(dir_name, 0755)
            os.chown(dir_name, uid, -1)

        with open(log_file, "w") as f:
            f.write("")

    os.chown(log_file, uid, -1)
    os.chmod(log_file, 0640)