Find the ferquency of values within an interval in Pandas Dataframe Column

Question

I have a pandas dataframe and a column in the dataframe has these values.

df['column'] = [84.0, 85.0, 75.0, nan, 51.0, 50.0, 70.0, 85.0 ... ]

I am trying to get the frequency of getting a value between an interval like

freq = {
    15 : 40,  # number of values between 10 and 20 were 40. (mean taken to be 15)
    25 : 47,  # number of values between 20 and 30 were 47. (mean taken to be 25)
    ...
}

Is there any specific function in pandas to do this kind of operation rather than making a for loop and checking each value and incrementing the count in the freq dictionary?

[Edit] my goal is to get a dictionary like this and then to replace NaN with freq.keys() in the ratio of freq.values()

Thank you