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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def upload_vcl(self, service_id, version_number, name, content, main=None, comment=None):
 		"""Upload a VCL for a particular service and version."""

		body = self._formdata({
			"name": name,
			"content": content,
			"comment": comment,
			"main": main,
		}, FastlyVCL.FIELDS)
		content = self._fetch("/service/%s/version/%d/vcl" % (service_id, version_number), method="POST", body=body)
		return FastlyVCL(self, content)