def set_clim(self, vmin=None, vmax=None):
if (vmin is not None and vmax is None and<EOL>cbook.iterable(vmin) and len(vmin)==<NUM_LIT:2>):<EOL><INDENT>vmin, vmax = vmin<EOL><DEDENT>if vmin is not None: self.norm.vmin = vmin<EOL>if vmax is not None: self.norm.vmax = vmax<EOL>self.changed()<EOL>
set the norm limits for image scaling; if *vmin* is a length2
sequence, interpret it as ``(vmin, vmax)`` which is used to
support setp

ACCEPTS: a length 2 sequence of floats