def __call__(self, x, pos=0):
    'Return the label for time *x* at position *pos*'
    ind = int(round(x))
    if ((ind >= len(self.t)) or (ind <= 0)):
        return ''
    dt = num2date(self.t[ind], self.tz)
    return cbook.unicode_safe(dt.strftime(self.fmt))
Return the label for time *x* at position *pos*
def __call__(self, x, pos=0):
    
    ind = int(round(x))
    if ((ind >= len(self.t)) or (ind <= 0)):
        return 
    dt = num2date(self.t[ind], self.tz)
    return cbook.unicode_safe(dt.strftime(self.fmt))