with open('saurav_BPF.txt','r') as myfile:
    f = myfile.read()
    st = f.splitlines()
st = list(map(float, st))  # converting str in a list to float
tr = st[0]
npts = tr.stats.npts
dt = tr.stats.delta
t = np.linspace(0, dt * npts, npts)

Traceback (most recent call last):
  File "cwt_trial.py", line 16, in <module>
    npts = tr.stats.npts
AttributeError: 'float' object has no attribute 'stats'