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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Notebook 3.3
Step1:  Newick tree files
We learned in notebook 3.2 that the file format to store phylogenetic trees is simply a text file containing a string of names within nested parentheses. When researchers publish phylogenetic results these are the types of tree files that they produce and publish. The files are sometimes saved as something like "treefile.newick" or "trees.nwk" or "birds.tree", etc. There are databases online where such files are saved including those that are specialized for tree data (like TreeBase) or general data repositories like Data Dryad. 
Newick trees
The toytree.tree() function reads the newick file to create a Tree object in memory. As input it can take a newick string as text, or it can take a URL pointing to a text file online, or it can take a filename that is located on your computer.
Step2:  An example using a URL from treebase
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Python Code:
import toytree
Explanation: Notebook 3.3: Newick Assignment
Complete the notebook then download as an HTML file (toolbar -&gt; File -&gt; Download as) and submit your assignment by emailing to Natalie (natalie.niepoth@columbia.edu).
End of explanation
newick = "((a,b),(c, d));"
tre = toytree.tree(newick)
tre.draw();
Explanation: Newick tree files
We learned in notebook 3.2 that the file format to store phylogenetic trees is simply a text file containing a string of names within nested parentheses. When researchers publish phylogenetic results these are the types of tree files that they produce and publish. The files are sometimes saved as something like "treefile.newick" or "trees.nwk" or "birds.tree", etc. There are databases online where such files are saved including those that are specialized for tree data (like TreeBase) or general data repositories like Data Dryad. 
Newick trees
The toytree.tree() function reads the newick file to create a Tree object in memory. As input it can take a newick string as text, or it can take a URL pointing to a text file online, or it can take a filename that is located on your computer.
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URL = "https://treebase.org/treebase-web/search/downloadATree.html?id=11298&treeid=31264"
tre = toytree.tree(URL)
tre.draw(tip_labels_align=True, height=800, width=600);
Explanation: An example using a URL from treebase
End of explanation
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