[BUG] ET_Email() return only one email record.

[QimanWang]

Describe the bug
A clear and concise description of what the bug is.
ET_Email() seems to only return one record, instead of the whole list of emails.
To Reproduce
Steps to reproduce the behavior.
running https://github.com/salesforce-marketingcloud/FuelSDK-Python/blob/master/objsamples/sample_email.py
Expected behavior
A clear and concise description of what you expected to happen.
will return only one email record.
Screenshots
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Code snippet
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Environment

• SDK Version [e.g. 1.2.0]
• Python version 3.7

The bug has the severity

• Critical: The defect affects critical functionality or critical data. It does not have a workaround.
• Major: The defect affects major functionality or major data. It has a workaround but is not obvious and is difficult.
• Minor: The defect affects minor functionality or non-critical data. It has an easy workaround.
• Trivial: The defect does not affect functionality or data. It does not even need a workaround. It does not impact productivity or efficiency. It is merely an inconvenience.

Additional context
Add any other context about the problem here.
Does this have anything to do with email object moving from SOAP to REST?