title: Assign schema to pa.Table.from_pandas()
body: <p>Im getting this error when transforming a pandas.DF to parquet using pyArrow:</p>
  
  <pre><code>ArrowInvalid('Error converting from Python objects to Int64: Got Python object of type str but can only handle these types: integer
  </code></pre>
  
  <p>To find out which column is the problem I made a new df in a for loop, first with the first column and for each loop adding another column. I realized that the error is in a column of <code>dtype: object</code> that starts with 0s, I guess that's why pyArrow wants to convert the column to <code>int</code> but fails because other values are <code>UUID</code> </p>
  
  <p>Im trying to pass a schema: (not sure if this is the way to go)</p>
  
  <pre><code>table = pa.Table.from_pandas(df, schema=schema, preserve_index=False)
  </code></pre>
  
  <p>where schema is: <code>df.dtypes</code></p>