import os

directory = os.path.normpath("file path to folder")
for subdir, dirs, files in os.walk(directory):
    for file in files:
        if file.endswith(".txt"):
            f=open(os.path.join(subdir, file),'r')
            a = f.read()
            print a
            r = requests.post(url1,data=a).content
            file = 'file path to write api response'
            f = open(file, 'a+')
            f.write(r)
            f.close()