def teff(cluster):
b_vs, _ = cluster.stars()<EOL>teffs = []<EOL>for b_v in b_vs:<EOL><INDENT>b_v -= cluster.eb_v<EOL>if b_v > -<NUM_LIT>:<EOL><INDENT>x = (<NUM_LIT> - b_v) / <NUM_LIT><EOL><DEDENT>else:<EOL><INDENT>x = (<NUM_LIT> - math.sqrt(<NUM_LIT> + <NUM_LIT> * b_v)) / <NUM_LIT><EOL><DEDENT>teffs.append(math.pow(<NUM_LIT:10>, x))<EOL><DEDENT>return teffs<EOL>
Calculate Teff for main sequence stars ranging from Teff 3500K - 8000K. Use
[Fe/H] of the cluster, if available.

Returns a list of Teff values.