instructions
============
1) put unwise_psf/py in your PYTHONPATH
2) set the environment variable WISE_PSF_DIR to the unwise_psf/py/unwise_psf/data directory

examples
========
import unwise_psf.unwise_psf as unwise_psf
psf_w1 = unwise_psf.get_unwise_psf(1, '0000m016')
psf_w2 = unwise_psf.get_unwise_psf(2, '0000m016')
psf_w3 = unwise_psf.get_unwise_psf(3, '0000m016')
psf_w4 = unwise_psf.get_unwise_psf(4, '0000m016')

psf_w1_small = unwise_psf.get_unwise_psf(1, '0000m016', sidelen=51)

dependencies
============
astrometry.net
numpy
fitsio
scipy
pkg_resources

note about Python versions
==========================
this code was originally developed and tested with Python 2.7.12, but has since been modified for Python 3 by Dustin Lang

@MISC{2019ascl.soft01004M,
   author = {{Meisner}, A. and {Schlafly}, E.},
    title = "{unwise\_psf: PSF models for unWISE coadds}",
 keywords = {Software },
howpublished = {Astrophysics Source Code Library},
     year = 2019,
    month = jan,
archivePrefix = "ascl",
   eprint = {1901.004},
   adsurl = {http://adsabs.harvard.edu/abs/2019ascl.soft01004M},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}