Write weights in cooler

[Jelena4]

Hi,

When using the code below from issue #103, how would I also write the weights in the new cooler file?

c = cooler.Cooler('no_chrM.cool')
chromsizes = cooler.util.fetch_chromsizes('mm9')[:'chrY']
bins_without_chrM = cooler.binnify(chromsizes, binsize)

chunksize = 10000000
spans = cooler.tools.partition(0, len(c.pixels()), chunksize)
def chunk_generator():
for i, (lo, hi) in enumerate(spans):
print('chunk', i)
pixels = c.pixels()[lo:hi]
# only necessary if there are chrM hits
pixels = cooler.annotate(pixels, c.bins()[['chrom']], replace=False)
pixels = pixels[(pixels.chrom1 != 'chrM') & (pixels.chrom2 != 'chrM')]
yield pixels
cooler.io.create(<output_file>, bins_without_chrM, chunk_generator())