Get Data Grouped By Month in Pandas

monthly_resample.py

import pandas
import numpy

def resampled_data(query, date_col, target_col, period="M"):
    """ Function that takes an sql query and returns the sum of a target column
        by a period. Useful for getting monthly data
    """

    df = pandas.read_sql(query, conn)
    df.set_index(df[date_col], inplace=True)
    df.index = pandas.to_datetime(df.index)

    data = df[target_col].resample(period, how='sum').values
    data = data[~numpy.isnan(data)]
    return data