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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 _starts_with_drive_letter(self, file_path):
 """Return True if file_path starts with a drive letter. Args: file_path: the full path to be examined. Returns: `True` if drive letter support is enabled in the filesystem and the path starts with a drive letter. """

        colon = self._matching_string(file_path, ':')
        return (self.is_windows_fs and len(file_path) >= 2 and
                file_path[:1].isalpha and (file_path[1:2]) == colon)