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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_content_type(content_type):
 """Extract the MIME type value from a content type string. Removes any subtype and parameter values that may be present in the string. Args: content_type: str String with content type and optional subtype and parameter fields. Returns: str: String with only content type Example: :: Input: multipart/form-data; boundary=aBoundaryString Returns: multipart/form-data """

    m = email.message.Message()
    m['Content-Type'] = content_type
    return m.get_content_type()