====== Python Script for Generating Pre Mainsequence Models ======

This file is a Python script designed for astrophysics research, particularly in the area of star formation and evolution. It takes a chemical composition file as input, along with parameters defining a range of stellar masses, and generates pre-mainsequence models for this range. These models simulate the early stages of star formation before the stars begin fusing hydrogen in their cores. The script relies on the `pysep` package for processing the input and generating the models, and utilizes `numpy` for handling numerical ranges.

<code python>
from pysep.opac.tops import open_and_parse
from pysep.newpoly.popFileToPolyModel import generate_prems_models

from numpy import arange
import argparse

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Generate pre mainsequence models given a chemical composition file for a range of masses")
    parser.add_argument("path", help="path to chemical composition file", type=str)
    parser.add_argument("mlow", help="low mass range of pre main sequence models to generate", type=float)
    parser.add_argument("mhigh", help="high mass range of pre main sequence models to generate", type=float)
    parser.add_argument("mstep", help="step size betweem pre main sequence masse", type=float)
    parser.add_argument("-o", "--output", help="directory to output pre main sequence models too", type=str, default=".")
    parser.add_argument("-c", "--compName", help="Composition name to use in the premain sequence model", type=str, default="comp")

    args = parser.parse_args()
    masses = arange(args.mlow, args.mhigh, args.mstep)

    parsed = open_and_parse(args.path)

    generate_prems_models(parsed, masses, args.output, compName=args.compName, DDAGE=1000)


</code>