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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 get_issue(self, issue_id, params=None):
 """Returns a full representation of the issue for the given issue key. The issue JSON consists of the issue key and a collection of fields. Additional information like links to workflow transition sub-resources, or HTML rendered values of the fields supporting HTML rendering can be retrieved with expand request parameter specified. The fields request parameter accepts a comma-separated list of fields to include in the response. It can be used to retrieve a subset of fields. By default all fields are returned in the response. A particular field can be excluded from the response if prefixed with a "-" (minus) sign. Parameter can be provided multiple times on a single request. By default, all fields are returned in the response. Note: this is different from a JQL search - only navigable fields are returned by default (*navigable). Args: issue_id: params: Returns: """

        return self._get(self.API_URL + 'issue/{}'.format(issue_id), params=params)