Json Error

import sendgrid
from sendgrid.helpers.mail import Content, Email, Mail

sg = sendgrid.SendGridAPIClient("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")
from_email = Email("my@gmail.com")
to_email = Email("your@gmail.com")
subject = "A test email from Sendgrid"
content = Content(
    "text/plain", "Here's a test email sent through Python")

mail = Mail(from_email, subject, to_email, content)
response = sg.client.mail.send.post(request_body=mail.get())

# The statements below can be included for debugging purposes
print(response.status_code)
print(response.body)
print(response.headers)