Authenticate aws configure credentials inside Docker - python-3.x

Question

I wrote a python flask API that takes an image as an input, uploads it on an S3 bucket and then process it in a function. When I run it locally, it works just fine. But when I run it through Docker image, it gives botocore.exceptions.NoCredentialsError: Unable to locate credentials.
My python code:
import boto3
s3BucketName = "textract_bucket"
region_name = 'ap-southeast-1'
aws_access_key_id = 'advdsav',
aws_secret_access_key = 'sfvsdvsdvsdvvfbdf'
session = boto3.Session(
aws_access_key_id = aws_access_key_id,
aws_secret_access_key = aws_secret_access_key,
)
s3 = session.resource('s3')
# Amazon Textract client
textractmodule = boto3.client('textract', region_name = region_name)
def extract_text(doc_name):
response = textractmodule.detect_document_text(
Document={
'S3Object': {
'Bucket': s3BucketName,
'Name': doc_name,
}
})
extracted_items = []
for item in response["Blocks"]:
if item["BlockType"] == "LINE":
extracted_items.append(item["Text"])
return extracted_items
The flask API:
#app.route('/text_extract', methods = ['GET', 'POST'])
def upload_file():
if request.method == 'POST':
img = request.files['file']
file = secure_filename(img.filename)
bucket.Object(file).put(Body=img)
output = extract_text(file)
return {'results': output}
app.run(host="0.0.0.0")
Dockerfile:
FROM python:3.7
RUN apt update
RUN apt install -y libgl1-mesa-glx
COPY ./requirements.txt /app/requirements.txt
WORKDIR /app
RUN pip install -r requirements.txt
COPY . /app
EXPOSE 5000
ENTRYPOINT [ "python" ]
CMD [ "app.py" ]
The docker commands that I ran are:
docker build -t text_extract .
and then: docker run -p 5000:5000 text_extract
When I run the API and do a post request, I get the botocore.exceptions.NoCredentialsError error.
How can I fix this? Thanks